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MOTION-PICTURE  WORK 


A  GENERAL  TREATISE  ON  PICTURE  TAKING,  PICTURE 

MAKING,    PHOTO-PLAYS,    AND    THEATER 

MANAGEMENT  AND  OPERATION 


By 

DAVID  S.    HULFISH 

TECHNICAIi  EDITOR,   "moTOGRAPHy";  TELEPHONE  AND  MOTION 

PICTURE  expert;  solicitor  of  patents 


ILLUSTRATED 


CHICAGO 

AMERICAN  SCHOOL  OF  CORRESPONDENCE 

1913 


Copyright,  1913 

BY 

American  School  of  Correspondence 


Entered  at  Stationers'  Hall,  London 
All  Rights  Reserved 


So 


CONTENTS 


The  page  numbers  of  this  volume  ivill  be  found  at  the  bottom  of  the  pages; 
the  numbers  at  the  top  refer  only  to  the  section. 


PART  I 

THE  OPTICAL  LANTERN 

Page 

THE   ELEMENTS   OF   THE   LANTERN 11 

The  optical  system 12 

The  inverted  sHde 13 

Placing  slide  in  holder 14 

Thumb  spots 14 

THE   LAMP 15 

Acetylene 16 

Lime  light 16 

The  electric  arc 17 

Direct-current  arc 17 

Stereo  vs.  motion  arc 19 

Alternating-current  arc 19 

Lamp  adjustments 20 

Angle  of  carbons 21 

Centering  the  light 22 

Focusing  the  light 23 

LAMPHOUSE 24 

Pinhole  image  on  peephole  glass 24 

Shding  house 24 

Ventilation 25 

Guard 25 

CONDENSERS 25 

Development •  •  25 

Condenser  a  part  of  the  lens 28 

Plano-convex  condensers  in  pairs 28 

Focal  lengths 29 

Adjustment  for  slides  or  motion  head 30 

Diffusion  projection 31 

Adjustment  of  the  optical  system 31 

THE   SLIDE   CARRIER 33 

Simple  form  of  carrier 33 

Carriers  for  American  and  foreign  slides 34 

654579 


2  CONTENTS 

THE  SLIDE  CARRIER  Page 

Slide  window  masks 34 

Slide  window  shutters 35 

Slip  slide  carrier 35 

Mechanical  slide  changers 36 

Storage  of  slides 37 

DISSOLVING   LANTERNS 37 

Triple  lantern 37 

Double  lantern 39 

Lining  up  the  double  lantern 41 

Alignment  masks 42 

Dissolving  shutters 42 

Equipment  of  the  second  lantern 43 

Operation  of  the  double  lantern 43 

Single-lantern  dissolvers 43 

Precautions  in  dissolving 44 

Reversals 44 

Slide  alignment 45 

Speed  of  change 46 

THE   MOTION-HEAD   LANTERN 47 

Auxiliary  rheostat 47 

Auxiliary  rheostat  for  the  double  lantern 48 

Auxiliary  switch 49 

THE   LENS •. 51 

Lens  corrections 51 

Lenses  for  given  requirements 53 

Length  of  lens  focus 54 

Lens  table 54 

Estimating  lens  length 57 

Calculating  lens  data  without  the  table 57 

Accurate  calculations 60 

Lens  construction  and  adjustments 61 

Care  of  lenses 61 

FOCUSING 62 

Curvature  of  image 64 

Remedy  for  curvature 65 

Inclined  optical  axis 65 

The  keystone  picture 67 

Remedy  for  the  keystone  picture 68 

Lens  angle 69 

Inclined  screen 70 

The  keystone  mask 71 

LANTERN   SLIDES 72 

Emergency  slides 72 

Repair  of  slides 73 


I 


CONTENTS  3 

MOTION   HEAD  Page 

PORTRAYAL   OF   MOTION 75 

Proof  of  motion 76 

Perfected  motion  picture 77 

Viewing  devices 80 

Persistence  of  vision 81 

Projection  by  persistence  of  vision 82 

Motion  mechanism 83 

OPTICAL   SYSTEM    FOR   MOTION    PICTURES 84 

Lamp 84 

Condensers 84 

Short  rules  for  condenser  lengths 88 

Lenses 88 

Accurate  calculations 92 

Approximate  calculations 92 

Calculations  compared 93 

Matched  lenses — stereo  and  motiton  head 93 

Adjustable  lenses 94 

THE   SHUTTER 95 

Types  of  shutters 97 

Setting  the  shutter 99 

Fire  shutter 100 

FILM    GATE 100 

Functions 100 

Construction 101 

Adjustment  of  tension  springs 101 

Care 101 

FILM   SHIFT   OR   INTERMITTENT   MOVEMENT 102 

Intermittent  sprocket 102 

Geneva  or  pin-and-star 102 

Double  star 104 

Double  pin , 104 

Pitman 104 

Ratchet 105 

Drunken-screw 105 

Snail ■ 106 

Spring  latch 106 

Single-sprocket 107 

Modified  drunken  screw .^ 107 

Eccentric  sprocket 108 

Pin  cross 108 

Pin 109 

Claw 112 

Beater 113 

Intermittent  grip 115 

Adjustment  of  intermittent  movements 116 


4  CONTENTS 

Page 

CONTINUOUS    PROJECTION 118 

Duplex  projection 118 

Mox-ing  lenses 119 

Moving  mirrors 120 

Moving  prisms 121 

Steady  feed  elements 121 

THREADING   UP   THE   MOTION    HEAD 122 

Feed  reel 122 

Feed-reel  magazine 122 

Upper  steady  feed 122 

Upper  feed  loop 123 

Film  steady  drum 123 

Film  gate 123 

Intermittent  sprocket 123 

Lower  feed  loop 124 

Lower  steady-feed  sprocket 124 

Take-up  reel 124 

Framing  devices 125 

Rewinding 126 

Automatic  rewind 126 

Film  basket,  or  molasses  can 127 

Operator's  control  of  the  picture 128 

Motor  vs.  crank 128 

FILM 129 

Care  of  film  in  projecting 129 

Care  of  film  in  rewinding 130 

Care  of  film  in  storage 130 

Care  in  handling  film 130 

Packing  for  shipment 130 

Repair  of  films 130 

Film  splicing 131 

Titles 133 

Leaders  and  tails 133 

\Yarped  film 134 

OPERATOR'S   DUTIES 134 

Before  the  show  begins 134 

Preparing  for  projection 135 

Conducting  the  program 135 

Keeping  up  with  the  times 137 

SPECIFIC   PROJECTING   MACHINES 141 

Introduction 141 

THE   EDISON   KINETOSCOPE 143 

Installation 143 

Operation 147 

Take-up  device 148 

Wiring » 149 

Six  Edison  rules 151 


CONTENTS  5 

THE  EDISON  KINETOSCOPE  Page 

Calcium  or  gaso-oxygen  light 152 

Threading  up  the  film 152 

Film  winder 154 

Edison  film  mender 155 

Operating  gaso-oxygen  light 155 

Gaso-oxygen  saturator  and  burner 158 

Automatic  shutter 159 

Rheostats 160 

THE   MOTIOGRAPH IGl 

How  to  install  or  set  up  the  Motiograph 161 

Motiograph  lens  adjustment 166 

Threading  the  film 167 

Instructions 170 

Setting  the  Motiograph  shutters 174 

POWERS'   NO.   5   CAMERAGRAPH 189 

Intermittent  mechanism 191 

Framing  mechanism .^ 191 

Upper  reel  hanger • 192 

Lamphouse 192 

Lamp 193 

Safety  shutters 194 

Index  of  parts 197 

POWERS'   NO.   6   CAMERAGRAPH 200 

Intermittent  mechanism 201 

Shutter 201 

Film  feed 204 

Lamphouse 206 

PATHE   PROFESSIONAL   MODEL   PROJECTOR 206 

Intermittent  movement 207 

Shutter 208 

Film  feed 209 

Automatic  fire  shutter 210 

Lamphou.se 211 

Arc  lamp 211 

Care  of  machine 213 

Index  of  parts 215 

STANDARD   PROJECTOR 216 

Unique  feature 216 

Shutter 217 

Intermittent  movement 219 

Construction  of  motion  head 219 

Lamp 219 

Index  of  parts 220 

Threading  the  film 222 


6  CONTENTS 

Page 

REWINDING   STANDARD   PROJECTOR 223 

"Rewinding"  de\nce 224 

SELIG   POLYSCOPE 225 

Film  feed 225 

Lamphouse 228 

EDENGRAPH   PROJECTOR 229 

General  design 229 

Film  feed 229 

Motion  head 229 

Intermittent  drive 235 

Lamp 235 

LUBIN   PROJECTOR 235 

Safety  shutter 235 

Automatic  fire  shield 235 

Threading  film 236 

General  instructions 238 

The  rewinding  "standard"  projectdr 223 

The  Selig  polj^scope 225 

The  Edengraph  projector 229 

The  Lubin  projector 235 

TALKING   PICTURES 241 

Recording  sound 242 

Synchronism 242 

Length  of  records 244 

Unitary  machines 245 

Dependent  machines 249 

Dial-regulated  machines 251 

Small  subjects 255 

Large  subjects 256 

Talking-picture  camera 257 

Operation  of  the  Cinephone 258 

COLORMOTOGRAPHY 262 

Urban-Smith  process 268 

Making  Kinemacolor  film  pictures 263 

Production  of  color 264 

Alternate  projection 266 

Kinemacolor  machines 267 

Friese-Green  process 273 

Process  of  manufacture 274 

Projection  of  film 275 

Splices 276 

Color  shutter 276 

Development  of  system 276 

Film  manufacturers ' 277 


CONTENTS  7 

PART  II 

PHOTOGRAPHY  Page 

THEORY 11 

MECHANICAL   DETAILS 11 

Camera 11 

Pin-hole  image 11 

Inverted  image 12 

Buying  a  camera ,  .  .  13 

Construction  of  camera 14 

Lenses 14 

Shutters 24 

Plate-holder 26 

Routine  of  camera  operation 27 

PRODUCING   THE   IMAGE 28 

Principal  object 29 

Background 29 

Lighting 30 

Size  of  object 30 

Composition  and  balance 31 

Point  of  view 32 

Prominence  of  background 32 

Distortions 34 

Swing  back 34 

Rising  front 35 

RECORDING   THE   IMAGE 35 

Dry  plates y.  .  .  35 

Films 35 

Exposure 35 

Development 43 

Developing  formulas 48 

PRINTING 51 

Processes 51 

Printing-out  papers 52 

Self -toning  paper 55 

Developing  papers 56 

Lens  printing 58 

SPECIAL   APPLICATION   OF   PHOTOGRAPHY 61 

Lantern  slides 61 

Stereographs 62 

Panoramas 62 

Telephotographj- 63 

Orthochromatic  photography 64 

Colored  photographs 64 

Tri-color  photography 65 

Autochrome  plates 65 


8  CONTENTS 

MOTOGRAPHY  Page 

PRODUCT   DESIRED 69 

Chronophotography 69 

Kinephotography 70 

Subjects 71 

METHODS   OF   PRODUCTION 73 

Early  methods 73 

Modern  methods 75 

Division  of  labor 76 

THE   AUTHOR 76 

His  problems 77 

Specimen  scrips 78 

Drama 78 

Comedy 82 

Chase  and  trick  scrip 83 

Travel  scrip 90 

Travel  and  comedy  scrip 92 

Industrial  scrip 94 

Who  is  the  author 95 

THE   PRODUCER 95 

Studio  scenes 96 

Studio  lighting 101 

Pictures  without  studios 103 

Properties  and  costumes 105 

Actors 105 

Rehearsals 106 

Producing  a  drama 107 

THE   SALESMAN 112 

Branches  of  the  film  industry 112 

Selling  methods 112 

Lectures 112 

Release  dates 113 

Advance  shipments 114 

Factory  schedule 114 

Sales  contracts 115 

Title  posters 116 

THE   PHOTOGRAPHER 116 

Divisions  of  the  photographic  factory 116 

Raw  film 117 

Storage  of  film 119 

Perforation  of  film 119 

Camera  man 122 

Camera 122 

Camera  man's  duties 128 

Factory  floor  plan 140 

Development  of  films 141 


CONTENTS  9 

THE  PHOTOGRAPHER  Page 

Making  titles 143 

Printing 144 

Coloring  films 151 

Waterproofing 154 

Packing  films  for  shipment 154 

Reclaiming  waste 154 

PHOTOGRAPHIC   EQUIPMENT 155 

Buying  cameras 155 

Making  cameras 155 

Buying  films 155 

Fire  risk  in  storing  films 155 

CHRONOPHOTOGRAPHY 155 

Motographic  microscopy 156 

Motographic  ultramicroscopy 156 

X-Ray  motography 156 

TRICK   PICTURES 156 

Reversals 157 

Speed  pictures 157 

Dummies 157 

Ghosts 158 

Dissolving  views 159 

Double  printing 159 

Double  exposures 159 

Mirrors 160 

Blackroom 160 

Stop  picture 161 


MOTION   PICTURE   THEATER 

MANAGEMENT 165 

The  "sick"  motion-picture  theater 165 

Art  of  the  manager 169 

Reviving  a  "sick"  pictare  theater 170 

Competition 171 

Traffic 172 

Income  vs.  expense 172 

Managing  a  theater  for  profit 172 

STARTING   A   THEATER 173 

Selecting  a  location 173 

Financing 175 

A  store-front  city  theater  building 176 

Weekly  expense  sheet 183 

Special  buildings 188 

Weekly  expense  of  a  small  vaudeville  theater 189 


10  CONTENTS 

Page 

OPERATION 195 

Studying  audiences 195 

The  program 196 

Advertising 197 

Poster  service 198 

Electric  signs 198 

Announcement  slides 199 

Printed  programs 200 

Newspapers 200 

Handbills 200 

Noise  wagon 200 

Feature  films 200 

Special  programs 201 

Renting  films .' 202 

Song  slides 202 

Hiring  employes 202 

Automatic  music 203 

Vaudeville 203 

Keeping  accounts 203 

Dull  season 205 

Tickets  and  chopper 205 

Side  lines  for  profit 207 


ELECTRICAL  PRINCIPLES 

ELECTRICITY   IN    MOTION  —  ELECTRIC   CURRENTS 213 

Magnetic  effect  due  to  a  charge  in  motion 213 

Galvanic  cell .  214 

Shape  of  magnetic  field  about  a  current 217 

Measurement  of  electric  currents 218 

Electromotive  force  and  its  measurements 218 

Electromotive  forces  of  galvanic  cells 220 

Electrical  resistance 221 

Ohm's  law 222 

Internal  resistance  of  a  galvanic  cell 222 

Primary  cells 223 

Action  of  a  simple  cell 223 

Polarization 226 

Combination  of  cells 231 

Storage  battery 231 

Electromagnetism 232 

Magnetic  properties  of  a  loop  and  of  a  helix 232 

Rules  for  north  and  south  poles  of  a  helix 233 

Electromagnet 234 

Electric  bell 235 

Laws  of  current  flow 236 


CONTENTS  11 

ELECTRICITY  IN  MOTION  —  ELECTRIC  CURRENTS  Page 

Resistance 236 

Resistance  proportional  to  length 236 

Resistance  inversely  proportional  to  cross-section 237 

Calculation  of  resistance 239 

Applications  of  Ohm's  law 248 

Simple  applications 248 

Series  circuits 249 

Fall  of  potential  in  a  circuit 250 

Divided  circuits 252 

WIRING    METHODS 256 

Planning  an  installation 256 

Method  and  systems  of  wiring 257 

Location  of  outlets 258 

Feeders  and  mains 263 

Wiring  an  office  building 264 

Electric  current  supply 264 

Switchboard 264 

Character  of  load 265 

Feeders  and  mains 265 

Circuits  for  each  floor 265 

Interconnection  system 268 

Outlet  boxes,  cut-out  panels,  and  other  accessories 269 

Outlet  boxes 269 

Bushings 271 

Fuse-boxes,  cut-out  panels,  etc 272 

MISCELLANEOUS  APPLIANCES 275 

Ar  c  lamps 275 

Electric  arc 275 

Arc-lamp  mechanisms 277 

Motion-picture  accessories 280 

Arc  lamp 280 

Miscellaneous 281 

Mercury-arc  rectifiers 282 

REVIEW   QUESTIONS 287 

INDEX 285 


INTRODUCTION 

^^TXTY  years  ago  the  motion  picture  was  a  child's  toy.  Today 
it  is  the  basis  of  a  business  giving  profitable  employment  to 
thousands  of  workers,  offering  amusement  and  education  to  millions 
of  people,  and  involving  an  investment  of  capital  that  places  it 
among  the  world's  great  industries. 

^The  motion-picture  maker  sets  up  his  whirring  camera  in  the 
wilds  and  the  crowded  city  alike.  He  records  the  downfall  of  kings 
and  the  inauguration  of  presidents,  the  horrors  of  great  disasters 
and  the  deeds  of  popular  heroes;  he  spreads  before  us  in  moving 
panorama  all  that  is  interesting  in  nature  and  in  man's  work,  in 
drama  and  in  real  life.  Every  large  city  has  its  motion-picture  fac- 
tory, and  every  village  its  motion-picture  theater.  Into  communi- 
ties too  small  to  support  a  theater  regularly  comes  the  traveling 
exhibitor  with  his  portable  outfit,  and  shows  in  town  hall,  church, 
or  country  school  house. 

^  For  so  important  an  industry  a  book  of  reference  and  instruction 
is  more  than  merely  justified;  it  is  demanded.  The  motion-picture 
field  is  broadening  day  by  day;  the  details  of  the  business  are  becom- 
ing more  multitudinous  with  each  advance.  The  worker  in  one 
branch  of  activity  must  have  ^me  knowledge  of  all  the  branches 
to  be  able  to  get  the  best  results  in  his  owti  work.  This  treatise 
on  Motion-Picture  Work  is  the  first  compilation  to  cover  adequately 
the  entire  field. 


^Tlie  Art  of  the  motion  picture  comprises  two  principal  industries: 
the  manufacturing  and  the  exhibiting  of  film  pictures.  Both  of 
these  fields  are  covered  in  this  volume.  The  worker  in  either  field 
will  be  deeply  interested  in  the  detail  and  technique  of  the  other, 
and  will  profit  by  that  broader  knowledge.  The  beginner  requires 
a  complete  knowledge  of  both  branches  to  fit  himself  for  work  in 
either  branch. 

HThe  drawings,  diagrams,  and  photographs  incorporated  herein 
have  been  prepared  especially  for  this  work;  and  their  instructive 
value  is  as  great  as  that  of  the  text  itself.  They  have  been  used  to 
illustrate  and  expand  the  text,  and  not  as  a  medium  around  which 
to  build  the  text.  Both  drawings  and  diagrams  have  been  ren- 
dered as  simply  as  was  compatible  with  their  correctness,  with  a 
view  to  making  them  as  nearly  as  possible  self-axplanatory. 
][  Tliis  volume  is  a  compilation  of  many  of  the  most  valuable  Instruc- 
tion Papers  of  the  American  School  of  Correspondence,  and  the 
method  adopted  in  its  preparation  is  that  which  this  School  has 
developed  and  employed  so  successfully  for  many  years.  This 
method  is  not  an  experiment,  but  has  stood  the  severest  of  all  tests 
— that  of  practical  use — which  has  demonstrated  it  to  be  the  best 
yet  devised  for  the  education  of  the  busv  man. 


c 

5 


THE  OPTICAL  LANTERN 


INTRODUCTION 

The  optical  lantern  is  a  device  for  showing  an  enlarged  repro- 
duction of  a  small  picture  upon  a  screen  before  an  audience.  The 
small  picture  from  which  the  projection  is  made  is  most  conveniently 
a  transparent  picture,  formed  photographically  upon  glass  by  photo- 
graphic processes.  Modifications  of  the  lantern  may  be  made  to 
show  pictures  upon  opaque  surfaces,  such  as  newspaper  clippings  or 
souvenir  postcards,  or  may  show  projections  from  solid  objects. 
Still  another  modification  of  the  optical  lantern  is  that  in  which  the 
motion  head  with  its  strip  of  pictures  is  substituted  for  the  fixed  slide 
in  its  carrier,  and  motion  pictures  are  shown  upon  the   screen. 

The  lantern  consists  primarily  of  a  lamp  for  lighting  the  slide 
and  a  system  of  lenses  for  focusing  the  slide  upon  the  distant  picture 
screen.  A  slide  holder  is  provided  for  receiving  the  slide  and  is 
adapted  to  hold  it  in  position  in  the  lens  and  lamp  system.  A  lamp 
house  is  provided  for  the  lamp,  obscuring  all  light  except  that  which 
passes  from  the  lamp  through  the  slide  and  through  the  lens  system. 
The  lens  system  usually  is  divided,  one  part  being  placed  between 
the  lamp  and  the  slide,  and  the  other  part  being  placed  between  the 
slide  and  the  picture  screen  upon  which  the  image  of  the  slide  is  to 
be  projected.  The  lenses  between  the  lamp  and  the  slide  are  called 
the  condensers,  and  the  lenses  between  the  slide  and  the  picture 
screen  are  called  the  objective  lenses,  or  more  briefly,  the  lens. 

THE  ELEMENTS  OF  THE  LANTERN 

The  parts  going  to  make  up  the  complete  lantern  system  ready 
for  projection  may  be  listed  as  lamp,  lamphouse,  condenser,  slide, 
slide  holder,  lens,  and  screen.  The  complete  system  of  the  lantern 
is  shown  in  Fig.  1,  which  shows  in  diagram  the  elements  arranged 

Copyright,  1911,  by  American  School  of  Correspondence. 


11 


o  THE  MOTION  PICTURE 

in  their  proper  relation  when  in  use.  At  L  is  shown  an  electric  arc, 
in  the  lamphouse  LH.  In  the  front  of  the  lamphouse  is  mounted 
the  condenser  C,  consisting  of  two  condenser  lenses  in  a  frame.  In 
front  of  the  condenser  C  is  the  slide  holder  SH  and  in  it  the  slide 
SL.  In  front  of  the  slide  holder  and  its  slide,  and  at  a  litUe  distance, 
is  the  objective  lens  O,  while  at  the  extreme  right  is  the  picture  screen 
PS,  upon  which  the  lens  O  concentrates  in  focus  the  light  received 
from  the  lamp  L  through  the  condenser  C  and  slide  SL. 

The  Optical  System.  The  light  originates  at  L,  and  it  is  desired 
to  get  as  much  as  possible  of  that  light  upon  the  screen  PS.  For 
that  purpose,  the  system  of  lens  glasses  is  used.  Projection  with- 
out lenses  is  possible,  but  not  in  any  way  practicable.  To  collect  as 
much  as  possible  of  the  light  of  the  lamp  L,  a  lens  glass  having  a 
large  surface  is  placed  near  the  lamp.  This  is  the  back  condenser 
lens,  or  left  lens  of  the  two  in  the  condenser  case  at  C.     All  the  light 


x_\ 


/^s 


Fig.    1.     Complete  Optical  System  of  the  Ijantem 

falling  upon  the  flat  surface  of  the  back  condenser  lens  is  bent  into 
substantially  straight  lines,  and  thrown  upon  the  curved  surface  of 
the  front  condenser  lens.  The  front  condenser  bends  the  rays  of 
light  again  and  causes  them  to  converge  at  the  point  of  the  focal 
center  of  the  objective  lens  O,  where  they  cross  and  proceed  to  the 
picture  screen  PS.  The  distribution  of  the  light  upon  the  picture 
screen  by  the  condenser  lenses  and  the  objective  lens,  without  a  slide 
in  the  holder,  is  perfectly  uniform  when  lamp  and  lenses  are  properly 
adjusted.  When  a  picture  slide  SL  is  placed  in  the  holder  SH,  some 
of  the  light  is  obstructed  by  the  darker  spots  of  the  picture  while 
nearly  the  full  intensity  of  the  light  is  permitted  to  pass  through  the 
transparent  portions  of  the  slide.     The  result  is  that  the  picture  of 


12 


OPTICAL  LANTERN  3 

the  slide  is  transferred  to  the  picture  screen  in  the  form  of  a  shadow 
of  the  shde,  and  in  much  enlarged  form.  To  secure  a  sharp  image 
of  the  picture  of'the  sUde  upon  the  screen  PS,  the  sUde  SL  must 
be  exactly  placed  in  the  cone  of  light  at  the  proper  distance  from  the 
lens  0.  This  distance  is  determined  by  the  amount  of  curvature 
of  the  glasses  of  the  lens,  a  dimension  which  is  called  the  "focal 
length"  of  the  lens.  For  a  fixed  slide  of  ordinary  size,  the  lens  is 
chosen  of  such  focal  length  that  the  slide  is  properly  placed  nearly 
against  the  face  of  the  condensers,  as  shown  in  the  diagram.  For 
microscopic  projection  a  lens  of  very  short  focus  is  chosen  and  the 
slide  is  placed  very  near  the  lens,  while  for  motion-picture  projection 
a  lens  is  chosen  having  about  one-third  the  focal  length  of  a  lens 
for  projecting  fixed  slides,  and  the  motion-picture  film  is  placed 
much  nearer  to  the  lens  and  much  farther  away  from  the  condenser 
than  is  the  slide  SL  in  the  diagram  of  Fig.  1.  The  length  of  the 
focus  of  the  lens  and  the  position  of  the  slide  being  determined,  the 
finer  and  final  adjustment  for  causing  the  slide  to  be  focused  properly 
upon  the  picture  screen  is  made  by  moving  the  lens  itself  slightly 
into  an  accurate  position  of  focus. 

The  Inverted  Slide.  From  Fig.  1  it  can  be  seen  that  the  ray  of 
light  which  passes  through  the  top  of  the  slide  SL  ultimately  reaches 
the  bottom  of  the  picture  screen  PS.  Likewise,  the  ray  of  light 
passing  through  the  bottom  of  the  slide  reaches  the  top  of  the  pic- 
ture screen,  and  all  intermediate  points  are  found  upon  the  picture 
screen  in  their  proper  order  and  in  inverted  relation  with  reference 
to  the  position  of  the  slide  in  the  holder  SH.  In  order  to  effect  the 
projection  of  the  picture  upon  the  screen  with  the  top  of  the  picture 
at  the  top  of  the  screen,  the  slide  is  inserted  in  the  holder  inverted. 

Not  only  is  the  slide  reversed  top  for  bottom,  but  it  is  reversed 
also  right  for  left.  A  square  slide  may  be  placed  in  the  slide  holder 
in  eight  different  positions,  only  one  of  which  is  correct.  The  Ameri- 
can standard  slide,  which  is  a  little  wider  than  it  is  high,  still  can  be 
placed  in  the  slide  holder  in  four  different  positions,  only  one  of 
which  is  correct.  In  strictly  picture  slides,  it  may  be  sufficient  to 
get  the  bottom  of  the  slide  at  the  bottom  of  the  screen,  but  where  there 
are  letters  or  words,  such  as  signs,  in  the  picture,  or  titles  written  or 
printed,  it  is  necessary  also  to  have  the  left  side  of  the  slide  at  the 
left  side  of  the  screen 


13 


4  THE  MOTION  PICTURE 

Placing  Slide  in  Holder.  The  simplest  rule  is  the  safest.  Take 
the  slide  in  the  left  hand  and  look  through  it,  holding  it  so  that  it  is 
correct,  top  at  top  and  left  at  left,  holding  it  by  the  upper  left-hand 

corner  and  viewing  it  as  it  is  to  be 
viewed  upon  the  screen  by  the 
audience.  This  position  of  the 
slide  and  of  the  left  hand  holding 
it  is  shown  in  Fig.  2.  Face  the 
screen  standing  at  the  side  of  the 
lantern,  and  with  the  right  hand 
take,  hold  of  the  lower  left-hand 
corner  of  the  slide.  This  position 
of  the  hands  is  shown  in  Fig.  3. 
Now  release  the  slide  with  the  left  liand  and  without  changing  the 
grip  turn  the  hand  with  the  slide,  keeping  the  same  side  of  the  slide 

toward  the  eyes,  so  that  the  slide 
is  held  inverted  as  shown  in  Fig. 
4;  still  facing  the  pieture  screen, 
drop  the  slide  into  the  carrier  and 
pnsh  the  carrier  into  place  in  the 


FIr.  2.     Method  of  Holding  and  Tumins 

the  Slide  for  Proper  Insertion 

Into  the  Lantern 


d 

V      ^^'T-'             ^ 

v-X- 

Figs.  3  and  4.     Method  of  Holdinc?  and  Turning  the  Slide  for 
Proper  Insertion  Into  the  Lantern 

slide  holder.    In  brief,  hold  it  so  that  it  "reads  right,"  catch  it  by  the 
lower  left-hand  corner  and  drop  it  into  the  currier. 

Thumb  Spots.  Finger  marks  on  the  face  of  the  slide  show  plainly 
on  the  picture  screen,  and  are  very  undesirable;  the  moral  is  to  clean 
the  slides  before  showing  them  the  first  time  and  then  to  keep  them 
clean  by  handling  them  only  by  the  edges  or  masked  margins  where 
finger  marks  if  any  will  not  show  upon  the  picture  screen.  The 
"thumb  spot,"  however,  is  a  different  matter.    In  Fig.  5,  at  the  upper 


14 


o 

^^^^®^ 

r  ^  ^  . 

OPTICAL  LANTERN  5 

right-hand  comer  of  the  figure  and,  therefore,  at  the  lower  left-hand 
corner  of  the  sHde  when  viewed  as  in  Fig.  2,  is  shown  a  small  circle 
or  spot.  This  is  the  thumb  spot,  and  if  the  thumb  of  the  right 
hand  is  placed  upon  this  spot  the  slide  will  go  into  the  carrier  properly 
inverted  and  will  appear  in  its  proper  position  on  the  screen.  Thumb 
spots  may  be  bought,  cut  from  gummed  paper,  as  circles  or  stars, 
or  may  be  clipped  square  from  paper  and  gummed  on.  The  ad- 
vantage of  the  thumb  spot  gummed  upon 
the  outer  surface  of  the  glass  is  that  it  may 
be  felt,  and  the  lantern  operator  knows 
without  looking  at  his  slide  that  it  is  in 
the  proper  position  and  will  appear  cor- 
rectly upon  the  screen.  The  disadvantage 
of  the  gummed  thumb  spot  is  that  it  some-       Fig.  5.    Thumb  Spot  on 

°  ^  the  Lantern  Slide 

times  comes  off. 

Another  method  of  p^o^•iding  for  the  thumb  spot  is  to  paste  it 
upon  the  mask,  or  upon  the  inside  of  the  glass  of  the  slide  (some 
masks  are  printed  with  thumb  spots  upon  them)  but  this  has  the 
disadvantage  of  requiring  the  operator  to  look  at  the  slide  to  find 
the  thumb  spot,  and  does  not  warn  him  automatically  by  touch  in 
case  one  slide  in  a  set  has  been  turned  accidentally  and  the  operator 
is  mechanically  feeding  through  the  set  after  having  tested  the  top 
slide  of  the  pile.  The  inside  thuml)  spot  cannot  be  lost  from  the 
slide,  and  may  be  supplemented  by  an  outside  spot  gummed  on  if 
the  operator  will  take  the  trouble. 

Where  slides  are  in  sets,  as  in  slides  for  illustrating  songs,  the 
slides  are  numbered,  the  thumb  spot  sometimes  being  used  for  the 
number  of  the  slide  in  the  series. 

THE  LAMP 

An  oil  lamp  is  sufficient  for  toys,  an  incandescent  gas  mantle 
or  an  incandescent  electric-lamp  bulb  for  a  parlor  exhibition.  For 
larger  rooms  requiring  a  longer  distance  from  the  lantern  to  the  pic- 
ture screen,  and  requiring  a  larger  picture  upon  the  screen  because 
of  the  greater  number  of  people  who  are  to  view  it  and  the  conse- 
quent greater  distance  from  the  screen  of  the  more  remote  spectators, 
a  brighter  illumiiiant  is  required.  This  is  found  in  acetylene  gas, 
in  the  lime  light,  or  in  the  electric  arc. 


15 


G  THE  MOTION  PICTURE 

Acetylene.  Acetylene  is  a  gas  produced  for  illuminating 
purposes  by  wetting  calcium  carbide  with  water.  It  produces  a 
very  brilliant  white  light,  suitable  for  lantern  projection,  but  not 
so  brilliant  as  the  calcium  light  or  the  electric  arc.  The  acetylene 
light  has  the  disadvantage  of  offering  a  comparatively  large  flame, 
whereas  the  calcium  light  (or  lime  light)  and  the  electric  arc  both 
offer  a  light  which  comes  from  a  very  small  surface,  practically  from 
a  single  point.  The  light  from  the  point  is  better  for  projecting 
purposes. 

Acetylene  generators  all  provide  a  water  tank  and  a  carbide 
chamber.  They  vary  in  the  method  or  means  for  admitting  small 
quantities  of  water  to  the  carbide  chamber  or  small  quantities  of 
carbide  to  the  water  tank.  In  some  generators,  the  water  is  carried 
to  the  carbide  by  soaking  up  a  wick,  the  amount  of  gas  generated 
being  regulated  by  the  speed  with  which  the  water  can  reach  the 
carbide  by  soaking  through  the  wick.  The  gas  must  be  used  as 
generated,  and  when  not  needed  the  generation  is  stopped  by  Hft- 
ing  the  wick  from  the  water.  In  others,  the  water  drops  upon  the 
carbide  through  a  needle  valve  which  is  capable  of  a  regulation  to 
give  exactly  the  flow  of  gas  required.  In  others,  the  carbide  is 
placed  in  a  floating  chamber  which  is  lifted  from  the  water  by  the 
generation  of  gas,  being  lowered  into  contact  with  the  water  again 
when  the  gas  is  used.  Any  generator  which  accumulates  gas  under 
pressure  is  more  dangerous  than  one  in  which  no  provision  is  made 
for  storing  the  gas,  and  the  gas  must  be  generated  exactly  as  recpiired. 
Any  gas  generator  suitable  for  supplying  gas  to  automobile  headlights 
is  suitable  for  supplying  gas  to  a  projecting  lantern,  and  the  tanks 
of  compressed  gas  much  in  favor  for  automobile  lamps  are  suitable 
also  for  projecting  lantems.  The  only  connection  required  between 
the  gas  supply  and  the  burner  is  a  single  flexible  rubber  tube. 

The  gas  burner,  designed  especially  for  projecting  lanterns,  has 
a  row  of  jets  in  a  straight  line,  placed  endwise  to  the  condenser.  These 
are  bunched  as  closely  as  possible,  a  group  of  four  or  six  in  a  line 
having  a  length  of  an  inch  or  an  inch  and  a  half.  A  reflector  also 
may  be  used. 

Lime  Light.  This  is  a  form  of  incandescent  gas  burner.  The 
"lime"  is  a  cylinder  of  lime  set  upon  a  pin  in  such  a  manner  that  it 
may  be  turned  and  raised  and  lowered  as  well.     A  gas  jet  plays  upon 


16 


OPTICAL  LANTERN  7 

it  and  heats  it  to  a  white  heat  at  the  point  where  the  flame  of  the  jet 
touches  the  hme.  The  glowing  Kme  gives  a  brilliant  white  light, 
all  the  light  proceeding  from  a  very  small  area  of  the  lime  cylinder. 
The  projection  from  such  a  light  is  very  good,  but  the  light  is  trouble- 
some and  to  a  great  degree  unreliable.  The  lime  bums  into  a  pit 
at  the  point  where  the  flame  touches  it,  and  must  be  turned  at  short 
intervals  to  bring  a  new  spot  under  the  flame.  If  not  turned,  the 
tongue  of  flame  will  be  turned  back  by  the  curved  walls  of  the  pit 
and  may  even  reach  to  the  back  condenser,  striking  it  and  cracking 
it.  Sometimes  also  the  lime  without  apparent  reason  splits  and 
falls  from  its  support.  That  means  stopping  the  show  until  a  new 
lime  has  been  placed  and  the  jet  again  properly  adjusted. 

The  gas  jet  used  for  the  lime  light  will  use  ordinary  illuminating 
gas  urged  to  a  greater  heat  by  a  jet  of  oxygen;  thus  two  rubber  tubes 
are  required  leading  to  the  lime-light  burner.  When  the  illuminating 
gas  is  not  available,  a  supply  of  hydrogen  and  oxygen  is  required,  or 
some  of  the  many  substitutes. 

For  many  years,  prior  to  the  commercial  exploitation  of  the 
electric-arc  lamp  for  the  projecting  lantern,  projection  before  audiences 
of  any  size  or  importance  was  made  almost  exclusively  with  the  lime 
light,  and  much  stage  lighting  for  theaters  was  done  with  it.  "In 
the  lime  light"  is  an  expression  not  yet  lost  to  the  language,  although 
electricity  long  since  has  routed  the  lime  light  from  the  theater.  In- 
structions for  the  proper  use  and  care  of  the  lime  light,  including 
the  making  of  the  burners  and  of  the  gases  to  be  used  in  the  burners 
gas  generators,  gas  washers,  gas  purifiers,  gas  saturators,  and  so  on 
in  innumerable  variation,  are  found  in  abundance  in  books  and 
magazines  of  a  decade  since,  but  the  general  subject  has  little  interest 
to  the  modern  optical-lantern  operator  or  motion-picture  projection 
operator. 

The  Electric  Arc.  The  only  modification  of  the  ordinary  elec- 
tric are  required  to  adapt  it  for  use  in  the  optical  lantern  is  to  make 
it  as  much  one-sided  as  possible,  that  is,  to  arrange  it  so  that  as  much 
of  the  light  as  possible  will  be  thrown  toward  the  condensers. 

The  Direct=Current  Arc.  The  positive  pole  is  connected  to 
the  upper  carbon  of  the  lamp,  the  negative  to  the  lower  carbon.  The 
carbons  are  placed  end  to  end  and  in  a  straight  line  except  that  the 
axis  of  the  lower  one  is  slightly  in  front  of  the  axis  of  the  upper  one. 


17 


THE  MOTION  PICTURE 


Tiv 


Ck     Mrtion-Picture  Arc 
for  Direct  Current 


that  is,  toward  the  condensers.  In  the  direct-current  arc,  a  ca\'ity  or 
crater  is  formed  in  the  positive  carbon.  The  crater  is  the  hottest  and 
brightest  point  in  the  lamp,  and  from  it  proceeds  the  greatest  amount 
of  light.     By  displacing  the  negative  or  lower  carbon  slightly,  say, 

an  eighth  of  an  inch,  the  positive  or  upper 
carbon  is  caused  to  burn  with  a  diagonal 
end  containing  the  brilliant  crater,  and 
the  light  of  the  arc,  therefore,  is  thrown 
off  to  one  side  of  the  lamp,  namely  to 
that  side  toward  the  condensers.  The 
proper  relation  of  the  carbons  is  shown 
in  Fig.  G,  and  the  direction  of  greatest 
intensity  of  light  is  shown  by  the  dotted 
lines  radiating  from  the  upper  carbon. 
To  bring  this  maximum  light  upon  the 
condenser  surface,  the  line  of  the  carbons  must  be  inclined  as  shown, 
and  at  about  the  same  angle,  say,  twenty  to  thirty  degrees.  If 
inclined  too  much,  the  end  of  the  lower  carbon  will  throw  a  shadow 
upon  the  condenser,  and  if  not  inclined  enough  the  greatest  bril- 
liancy upon  the  condenser  will  not  be  obtained.  In  this  connection 
it  may  be  noted  that  the  length  of  the  arc  governs  to  some  extent, 
the  angle  at  which  the  lamp  may  be  inclined,  since  with  a  longer 
arc  a  greater  inclination  may  be  had  before  the  lower  carbon  shades 
the  condenser  from  the  crater.  The  carbons  should  be  set  parallel 
If  set  at  even  a  slight  angle,  the  feed  as  the  carbons  bum  away  wil 

change  the  displacement  of  the  two  ends' 
^-"^-^     and  change  the  value  of  the  light. 

A  second  method  of  setting  the  carbon 
for    the   direct-current    arc  is  shown  in 
Fig.  7.     The  positive  carbon  is  set  hori- 
zontally and  when  properly  adjusted  for 
position,  points  directly  toward  the  center 
of  the  condenser,    ^^'hen  fed,  it  moves  di-., 
rectly  toward  the  condenser,  and  thus  al-| 
ways  keeps  its  crater  "centered,"  whereasft 
in  the  adjustment  of  Fig.  6,  the  burning  away  of  the  upper  carbon 
constantly  raises  the  crater  from  the  center  line  of  the  condenser,  and 
the  feeding  of  the  upper  carbon  constantly  lowers  the  crater.     Unless 


Fig.  7.     Stereopticon  Arc 
for  Direct  Current 


18 


f 


OPTICAL  LANTERN  9 

the  feed  is  exactly  proportioned  to  the  burning  away,  and  exactly 
compensates  for  the  burning  away,  the  crater  wili  get  off  the  axis 
of  the  condenser  and  the  lamp  as  a  whole  must  be  moved  to  bring 
it  back.  Unfortunately  the  adjustment  of  Fig.  7  does  not  give  as 
brilliant  an  arc  as  the  adjustment  of  Fig.  6  when  a  long  arc  is  used, 
but  when  a  short  arc  is  used  the  carbons  become  so  near  in  Fig.  6 
that  Fig.  7  becomes  preferable  and  gives  the  better  light. 

Stereo  vs.  Motion  Arc.  Fig.  7  is  called  the  stcrcopticon  arc, 
and  Fig.  6  is  called  the  motion-picture  arc.  Stereopticon  or  fixed- 
slide  projection,  with  the  large  shde  nearly  three  inches  square  and 
enlarged  to  nine  feet  square  on  the  screen,  requires  a  magnification 
of  thirty-six  diameters.  A  fifteen-ampere  arc  is  sufficient  to  give 
the  illumination  required;  a  forty-ampere  arc  gives  so  much  heat 
that  slides  will  be  broken  by  the  heat  if  left  in  the  slide  holder  for 
many  seconds.  With  a  fifteen-ampere  arc,  the  adjustment  of  Fig. 
7  gives  a  better  light  than  that  of  Fig.  6  because  in  Fig.  G  the  carbons 
are  brought  so  close  to  maintain  the  short  arc  that  the  lower  carbon 
shades  the  condenser.  ]\Iotion-picture  projection,  with  the  image 
only  three-quarters  of  an  inch  by  one  inch,  enlarged  to  seven  and 
one-half  by  ten  feet  on  the  screen,  requires  a  magnification  of  one 
hundred  and  twenty  diameters — more  than  three  times  the  lineal 
enlargement  and  more  than  ten  times  the  surface  enlargement  of  the 
stereopticon  projection.  A  forty-ampere  arc  is  desirable,  and  the 
longer  arc  adjustment  between  the  carbons  permits  the  adjustment 
of  Fig.  6  to  attain  the  greatest  possible  brilliancy  upon  the  condensers. 
The  heat  is  intense  and  would  ignite  the  celluloid  film  almost  in- 
stantly were  the  film  to  remain  at  rest  in  the  heat,  but  the  period  (if 
rest  of  the  film  is  only  one-fourteenth  of  a  second  for  each  picture,  a 
period  of  time  too  short  to  permit  it  to  begin  to  blaze. 

The  Alternating=Current  Arc.  Li  alternating  current  there  is 
neither  positive  nor  negative  pole,  and  both  carbons  are  alike  in  the 
lamp,  each  having  a  crater,  but  neither  crater  as  hot  for  the  same 
current  value  as  the  direct-current  crater  for  the  same  current. 
When  the  carbons  are  set  in  line,  the  light  of  the  alternating  arc  is 
distributed  equally  in  all  directions,  but  when  they  are  set  at  a  slight 
angle  to  each  other  the  greater  portion  is  thrown  outward  from  the 
angle.  The  proper  setting  is  shown  in  Fig.  8.  The  angle  there 
shown  is  about  as  great  as  will  be  found  possible  to  get  the  best  light, 


19 


10 


THE  MOTION  PICTURE 


Fi 


.  8.     Proper  Arc  for  Alterna- 
ting; Cun-ent,  with  Cored 
Carbons 


but  the  angle  between  the  carbons  depends  to  some  extent  upon  the 
amount  of  current  used  and  the  length  of  the  resulting  arc.  A  larger 
current  is  required  with  alternating  than  wath  direct  current,  from 
fifty  to  sixty  amperes  being  common. 

Cored  Carbons.  Carbons  are  made  either  with  the  same  con- 
sistency of  carbon  through  the  pencil  or  with  a  hard  shell  and  a 
soft  core,  the  core  being  about  the  size  of  the  lead  in  a  lead  pencil. 

When  the  cored  carbon  is  used,  the  crater 
will  form  in  the  end  of  the  core,  keeping 
in  the  center  of  the  carbon  pencil,  and 
the  vapor  of  the  soft  core  will  hold  the  arc 
between  alternations.  With  the  alterna- 
ting-current  arc,  the  cored  carbon  is  a 
necessity,  producing  the  arc  shown  in  the 
diagram  of  Fig.  8,  whereas  without  the 
cored  carbons  the  arc  has  a  tendency  to 
run  to  the  nearer  edges  of  the  carbons,  as  shown  in  the  diagram  of 
Fig.  9,  with  consequent  loss  of  brilliancy  upon  the  condensers.  The 
solid  carbon  is  generally  used  in  the  direct-current  arc.  For  one  reason, 
it  costs  less  money.  The  light  will  be  found  easier  of  control,  re- 
quiring less  skill  on  the  part  of  the  op- 
erator if  the  cored  carbons  are  used  on 
the  direct-current  arc  also.  Soft  carbons 
give  a  better  light  than  hard,  but  bum 
away  faster  and  require  more  attention 
and  adjustment. 

Lamp  Adjustments.  The  lamp  has  four 
adjustments:  (/)  vertical,  or  up  and 
down;  (.3)  focusing,  or  back  and  front, 
toward  and  from  the  condensers;  (J)  lateral,  or  right  and  left;  and 
(4)  feed. 

The  vertical,  focusing,  and  lateral  adjustments  for  the  position 
of  the  arc  are  mentioned  in  the  order  of  their  frequency  of  use.  The 
feed  is  the  adjustment  of  the  carbons  in  the  lamp,  and  should  take 
place  \vithout  changing  the  position  of  the  arc;  feed  provides  for  the 
burning  away  of  the  carbons  by  the  arc,  the  position  of  the  arc  being 
changed  independent  of  feed  by  the  three  remaining  adjustments. 
The  different  types  of  lamps  made  and  sold  by   different  raanu. 


FiS-  9-     Improper  Arc  for  Al- 

ternatin;^  CurreiU,  with 

Solid  Carbons 


20 


'OPTICAL  LANTERN  11 

facturers  vary  greatly  in  the  details  of  the  adjustments.  In  taking 
charge  of  a  lamp,  look  for  the  four  adjustments.  The  fourth  or 
feeding  adjustment  will  be  found  the  most  prominent,  being  the  one 
most  used.  Invariably,  it  is  controlled  by  a  knob  projecting  from  the 
back  of  the  lamphouse.  Turning  the  knob  in  one  direction  brings 
the  carbons  together  and  turning  in  the  other  direction  separates 
them.  To  start  or  "strike"  the  arc,  turn  the  knob  to  bring  the 
carbons  together,  when  a  slight  sputtering  and  a  dim  lig.ht  will  an- 
nounce that  the  carbons  are  in  contact;  then  reverse  the  knob  quickly 
for  a  part  of  a  turn  to  draw  the  carbons  apart.  The  current  will 
continue  to  flow  through  the  separated  carbons,  and  a  brilliant  arc 
will  be  formed.  The  proper  adjustment  is  the  brightest  arc  obtain- 
able, all  adjustments  being  considered.  This  is  not  the  longest  arc 
nor  the  shortest  arc.  With  the  long  arc  the  current  is  reduced  and 
the  intensity  of  the  light  of  the  crater  is  less;  wliile  with  the  short  arc 
the  intensely  brilliant  crater  is  concealed  between  the  two  carbons. 
As  the  carbons  bum  away,  the  arc  becomes  longer  and  weaker  and 
ultimately  will  "break"  and  die  out,  requiring  that  the  arc  be  "struck" 
again  by  feeding  the  carbons  down  into  contact  and  backing  away 
as  in  striking  the  arc  at  first.  The  carbons  must  be  fed  down  skill- 
fully to  compensate  for  the  burning  away  before  the  arc  breaks. 
The  feed  may  be  gauged  through  the  peephole  of  the  lamphouse,  or 
by  the  illumination  of  the  picture  screen,  or  by  the  sound  of  burning 
in  the  lamp.  At  frequent  intervals,  feed  downi  slowly;  the  illumina- 
tion of  the  screen  will  become  brighter  to  the  maximum  and  then 
lose  a  little,  indicating  by  the  slight  loss  that  the  proper  adjustment 
has  been  passed.  Then  back  up  slightly  to  the  best  adjustment  and 
after  a  half  minute  or  a  minute  feed  down  again  in  the  same  way. 
This  method  of  feeding  must  be  practiced  so  skillfully  that  the  audience 
will  not  notice  the  slight  changes  in  illumination  by  which  the  lan- 
tern operator  is  feeUng  the  pulse  of  the  arc. 

Angle  of  Carbons.  The  angle  at  which  the  carbon's  are  set  will 
vary  with  the  amount  of  current  used,  and  to  some  extent  with 
the  size  and  quality  of  carbons  used.  When,  looking  into  the  lamp- 
house,  the  front  wall  of  the  house  is  brighter  below  the  condensers 
than  above,  tip  the  carbons  to  a  greater  angle;  or  bring  them  more 
nearly  vertical,  when  the  inner  wall  of  the  lamphouse  shows  brighter 
above  the  condensers  than  below.     The  same  result  is  attained   by 


21 


12  THE  MOTION  PICTURE 

rocking  the  angle  of  the  carbons  while  watching  the  screen,  and 
stopping  where  the  illumination  is  brightest.  Care  should  be  taken 
in  practicing  with  the  adjustment  to  distinguish  between  the  effect 
on  the  screen  of  changing  the  angle  of  the  carbons  and  the  center- 
ing of  the  arc  itself. 

For  experiment,  open  the  door  of  the  lamphouse,  watch  the 
front  wall,  and  draw  the  arc  a  little  longer;  the  "brightest  spot" 
on  the  front  wall  moves  down,  because  by  drawing  the  arc  longer 
the  end  of  the  lower  carbon  has  been  drawn  from  in  front  of  the 
crater  of  the  upper  carbon.  To  bring  this  brightest  spot  back  to 
the  condensers,  the  carbon  must  be  tipj^ed  to  a  greater  angle.  But 
the  longer  arc  should  not  be  used  unless  there  is  current  to  support 
it  without  breaking.  The  production  of  a  steady  arc,  not  tjuite 
so  bright,  is  evidence  of  better  lamp  operating  than  a  brighter  but 
irregular  and  unreliable  arc — a  "forced"  arc.  The  amateur  always 
lacks  the  skill  required  to  force  an  arc  successfully;  the  master  of 
the  lantern  is  too  jealous  of  his  results  to  practice  it.  A  medium 
length  of  arc,  steady  of  feed  and  steady  in  illumination,  with  the  angle 
of  carbon  to  throw  the  brightest  spot  of  light  straight  into  the  con- 
densers, is  the  proper  adjustment.  Many  lanterns  do  not  have  the 
angle  of  carl)ons  adjustable  without  opening  the  lamphouse. 

Centering  the  Light.  The  proper  burning  of  the  lamp  will 
determine  the  brilliancy,  but  its  position  in  the  lamphouse  will 
govern  the  uniformity  of  the  illumination  of  the  screen.  There 
are  half  a  dozen  rules  for  centering  the  arc,  but  all  of  them  amount 
to  this:  The  screen  shows  the  arc  inverted  just  as  it  shows  the  lantern 
slides  inverted,  and  the  brightest  spot  on  the  screen  must  he  brought  to 
the  middh.  If  the  bright  spot  on  the  screen  is  above  the  center,  raise 
the  arc,  for  that  will  lower  its  image  on  the  screen.  If  the  arc  is  moved 
to  the  right,  the  bright  central  portion  of  the  light  on  the  screen  will 
move  to  the  left,  correspondingly .  Most  lanterns  have  the  vertical 
adjustment  possible  without  opening  the  lamphouse,  but  the  lateral 
adjustment  usually  requires  work  inside  the  lamphouse  door.  Once 
correctly  adjusted,  it  seldom  requires  changing. 

In  Fig.  10,  a  shadow  shows  at  the  left  of  the  screen,  the  center 
of  the  bright  image  of  the  arc  is  at  the  right  of  the  center  of  the  screen, 
and  the  arc  should  be  moved  to  the  right  in  the  lamphouse  to  bring 
the  bright  spot  on  the  screen  toward  the  left.     In  Fig.  11,  the  con- 


22 


OPTICAL  LANTERN 


13 


ditions  are  reversed,  the  shadow  is  at  the  right,  and  the  arc  should  be 
moved  to  the  left  to  throw  the  bright  spot  on  the  screen  to  the  right, 
pushing  the  shadow  off  the  screen.  In  Fig.  12,  the  shadow  is  at  the 
bottom,  and  the  arc  in  the  lamphouse  should  be  raised  to  lower  the 
bright  center  of  illumination  on  the  screen;  in  Fig.  13,  the  shadow  is 
at  the  t®p,  and  the  arc  in  the  lamphouse  should  be  lowered  to  raise 
the  bright  center  of  illumination  on  the  screen. 

Focusing  the  Light.  The  cone  of  light  passing  from  the  front 
of  the  condensers  should  come  to  a  point  at  the  focal  center  of  the 
objective  lens.  The  length  of  this  cone  may  be  changed  by  shifting 
the  light  back  and  forth  in  the  lamphouse,  hence  the  point  of  the 


Figs.   10-15.     Guide  Chart  for  Lamp  Adjustments 

Gone  may  be  brought  to  the  lens  after  the  position  of  the  lens  has  been 
determined.  To  find  the  proper  position  of  the  lens,  place  a  slide 
in  the  slide  holder  and  move  the  lens  to  focus  the  slide  upon  the 
picture  screen.  Then  remove  the  slide  and  adjust  the  lamp  to  that 
distance  from  the  condensers  which  will  bring  the  point  of  the  eone  of 
light  to  about  the  middle  of  the  lens  barrel.  The  final  adjustment 
for  position  of  the  lamp  is  determined  by  watching  the  picture  screen, 
and  the  symptoms  on  the  screen  are  illustrated  in  Figs.  14  and  15. 
With  a  bright  margin  upon  the  picture  screen  (no  slide  in  holder) 
and  with  a  central  shadow  or  with  a  ring  of  shadow  or  of  color  about 
the  center  of  the  screen,  the  lamp  is  properly  "centered"  but  is  too 


23 


14  THE  MOTION  PICTURE 

near  to  the  condenser.  This  is  shown  in  Fig.  14.  ^Vhen  the  lamp 
is  too  far  from  the  condenser,  the  edges  of  the  screen  will  be  in 
shadow  or  show  color.     This  is  shown  in  Fig.  15. 

LAMPHOUSE 

A  sheet-iron  house  or  box  contains  the  lamp  and  stops  its  light 
from  blinding  the  operator  and  from  illuminating  the  picture  screen 
with  the  stray  rays.  The  more  frequently  used  adjustments  of  the 
lamp  are  all  controlled  by  knobs  upon  rods  projecting  through  the 
rear  wall  of  the  lamphouse,  rendering  possible  all  adjustments  re- 
quired while  a  series  of  slides  are  being  shown,  or  while  a  motion- 
picture  reel  is  being  run,  without  opening  the  door  of  the  house. 
The  door  is  at  the  side  and  gives  access  to  the  lamp  for  the  purpose 
of  renewing  carbons  and  of  making  such  adjustments  as  ordinarily 
are  required  only  in  setting  up  the  lamp  for  service.  In  the  door  of 
the  lamphouse  is  a  peephole,  through  which  the  operator  may  look 
at  his  lamp  to  determine  whether  the  adjustment  is  approximately 
correct  before  projecting  the  light  upon  the  screen. 

Pinhole  Image  Peephole.  A  sheet-iron  box  an  inch  or  an  inch 
and  a  half  each  way  with  a  No.  60  drill  hole  in  the  middle  of  the 
bottom  and  the  open  top  placed  against  the  peephole  inside  the 
lamphouse  door  will  throw  a  pinhole  image  of  the  arc  and  carbon 
ends  upon  the  glass  of  the  peephole.  This  image  will  be  visible 
to  the  operator  from  any  angle,  and  it  is  not  required  that  the  eye  be 
brought  close  to  the  peephole,  nor  even  in  line*  with  the  peephole 
and  the  lamp. 

Sliding  House.  In  a  projecting  machine  adapted  for  motion 
pictures  and  lantern  slides,  the  same  lamphouse  is  used  for  the 
motion  head  and  for  the  long-focus  lens  for  fixed  slides.  With  the 
motion  head  and  the  long-focus  stereopticon  lens  mounted  upon  the 
projecting  stand  side  by  side,  the  lamphouse  is  slidable  upon  a  short 
track  so  that  it  may  be  pushed  from  the  motion  head  to  the  stere- 
opticon lens,  or  pulled  back  to  the  motion  head.  Stops  at  the  end 
of  the  track  are  adjustable,  for  centering  the  lamohouse  properly 
upon  the  motion  head  or  lens  at  its  two  positions. 

An  old  arrangement  is  to  have  the  motion  head  and  stereo  lens 
upon  a  pivoted  platform  which  swings  in  front  of  the  lamphouse  to 
bring  either  the  motion  head  or  the  stereo  lens  in  front  of  the  lamp. 


24 


OPTICAL  LANTERN 


15 


Ventilation.  Openings  in  the  bottom  and  in  the  top  of  the 
iamphouse  permit  a  current  of  air  to  carry  away  much  of  the  heat 
of  the  lamp.  A  precaution  to  be  observed  is  that  the  current  of  cold 
air,  incoming  through  the  bottom  holes,  does  not  strike  the  face  of 
the  condensers,  as  such  a  draught  may  crack  the  condensers.  Wire 
gauze  over  the  holes  in  the  bottom  of  the  Iamphouse  will  break  up 
the  incoming  column  of  air  and  usually  will  reduce  condenser  breakage. 

Guard.  The  top  of  the  Iamphouse  sometimes  gets  so  hot  that 
a  piece  of  motion-picture  film  will  burst  into  flames  when  touched 
to  the  house.  To  prevent  accidental  contact,  the  top  of  the  lamp- 
house  may  have  a  guard  of  wire  screen,  extending  over  the  edges. 

CONDENSERS 

The  object  of  these  large  glasses  in  the  optical  system  is  to  get 
more  light  into  the  lens  from  the  lamp.  Their  efficiency  is  so  great 
and  their  cost  is  so  low  that  all  lamp  systems  use  them — indeed,  it  is 
thought  by  operators  who  have  not  given  their  work  a  thought  that 
projection  without  condensers  is  quite  impossible.  A  very  good 
quality  of  projection  is  possible  without  condensers  when  using  a 
lantern  built  for  use  without  condensers.  Even  with  a  lantern  built 
for  use  with  condensers  it  is  possible  to  accomplish,  in  an  emergency, 
a  projection  which  may  serve  to  entertain  an  audience  and  save  the 
humiliation  of  dismissing  and  disappointing  the  people  altogether. 

Development.  The  development  of  the  condenser  as  it  is  gen- 
erally used   today  in  projecting  lanterns  is  shown  in  diagrams  in 


Z^z£3^^ 


Fig 


16.     Development  of  the  Modern  Type 
of  Condenser.     Double  Lens  Only 


Figs.  16  to  21,  inclusive.  Fig.  16  shows  a  system  in  which  the 
arc  lamp  at  the  left  throws  its  rays  directly  upon  the  slide  at  S. 
The  rays  of  the  lamp  pass  through  the  transparent  slide  and 
proceeding  then  in  straight  lines  pass  for  the  most  part  outside 
of  the  lens  at  L.     The   lens  gets  a  few  of   the   rays — that   small 


2S 


16 


THE  MOTION  PICTURE 


bundle  of  rays  passing  through  the  middle  of  the  slide  directly  in 
line  from  the  arc  lamp  to  the  lens — and  these  rays  the  lens  throws 
into  focus  upon  the  picture  screen  at  the  extreme  right  of  the 
diagram.  The  result  is  a  picture  upon  the  picture  screen  which 
covers  only  a  small  spot  in  the  middle  of  the  screen  and  which 
shows  in  that  spot  only  a  small  portion  of  the  slide,  the  central 
portion.  If  only  a  small  slide  were  used,  such  as  a  slide  from  a  toy 
lantern,  in  which  the  entire  picture  is  as  large  as  a  ten-cent  coin, 
the  entire  picture  of  this  diminutive  transparent  slide  at  the  left 
would  be  thro^\n  upon  the  picture  screen  at  the  right.  That  is  one 
type  of  projection  without  a  condenser.  The  slide  must  be  smaller 
in  size  than  the  lens  which  focuses  it  upon  the  screen,  so  that  all  the 
light  passing  through  the  slide  may  find  its  way  into  the  glasses  of 
the  lens.  When  it  is  desired  to  project  a  slide  in  which  the  picture  is 
three  inches  in  diameter  (and  the  usual  lantern  slide  is  about  that 


vd 


Fig.   17.  •  Development  of  the  Modem  Tj-pe  of  Con- 
denser (Rear  Combination  of  Lens  Enlarged) 

diameter  measured  from  corner  to  corner),  a  very  large  lens  would 
be  required.  Notice  also  that  the  light  after  pa.ssing  through  the 
slide  at  S  spreads  very  rapidly,  so  that  if  the  lens  were  placed  closer 
to  the  slide  the  lens  would  not  have  to  be  so  large  in  order  to  catch 
all  of  the  light  passing  through  the  sUde. 

A  modified  lens  is  shown  in  Fig.  17,  which  has  great  light- 
gathering  power  without  going  into  the  expense  of  several  large 
glasses.  One  of  the  glasses  of  the  lens  is  made  larger  than  the  slide 
to  be  projected  and  is  positioned  at  L-1  near  the  slide,  catching  the 
rays  soon  after  they  have  passed  through  the  slide  and  bending 
them  into  the  remaining  glass  of  the  lens,  shown  at  L-2.  In  this 
way,  practically  all  of  the  light  of  the  lamp  which  passes  through  the 
slide  is  caught  by  the  lens  L-1  and  is  bent  into  the  lens  L-2  and  thus 
is  brought  into  effect  in  producing  the  picture  upon  the  picture  screen 
at  the  right.     The  system  of  this  stage  of  development  is  further 


26 


1 


SCENE  FROM  PHOTOPLAY,  "THE  MASTER  AND  THE  MAN' 

Courtesy  of  Independent  Moving  Pictures  Co.,  New  York 


OPTICAL  LANTERN 


17 


improved  by  using  the  full  double  lens  at  the  point  L-2,  as  shown 
in  Fig  18,  the  large  lens  close  to  the  slide  being  thus  made  an  auxiliary 
piece  of  glass,  although  forming  a  part  of  the  total  lens  system.  Con- 
sidered as  a  glass  apart  from  the  lens,  and  seeking  a  name  for  it,  it 
is  noticed  that  it  has  the  power  of  gathering  the  light  coming  through 
the  picture  slide  and  squeezing  the  rays  together  or  condensing  them 


Fl?.    18.     Devplopment  of  the  Modem  Tyxte 
of  Condenser  (One  Condenser  Lens  Added) 

into  the  glasses  of  the  main  object  lens,  or  lens  proper,  L-2.  Con- 
sidered from  that  point  of  view,  the  name  of  "condenser"  appears 
to  be  fitted  to  the  glass  in  a  descriptive  way;  no  one  has  suggested 
a  better  name  for  it,  hence  "condenser"  it  is  called. 

With  the  auxiliary  lens  at  its  position  given  in  Fig.  18,  bending 
the  light  after  the  rays  have  passed  through  the  picture  slide,  it  is 
necessary  that  the  lens  be  of  a  high  grade  of  glass  and  that  it  be  very 
accurately  ground,  any  distortion  being  noted  upon  the  projected 
picture  at  the  right.  Experiment  shows  that  the  auxiliary  lens 
may  be  placed  upon  the  other  side  of  the  picture  slide,  as  shown 


Fig.  19      Development  of  the  Modern  Type 
of  Condenser  (Condenser  Behind  Slide) 

rearranged  in  Fig.  19;  that  in  that  position  it  is  ecjually  effective  in 
concentrating  the  light  into  the  lens  at  L,  and  that  when  so  placed 
its  slight  inaccuracies  are  not  so  clearly  visible  in  the  picture  at  the 
right,  which  is  the  picture  to  be  viewed  by  the  audience.  This 
permits  a  condenser  to  be  made  of  cheaper  glass,  and  with  less  ac- 
curate and  less  expensive  workmanship.  With  the  condenser 
placed  in  the  position  shown  in  Fig.  19,  the  condenser  may  be  said 


27 


18  THE  AIOTION  PICTURE 

to  condense  the  rays  into  the  lens  at  L,  but  the  optical  system  of  the 
lantern  may  be  better  studied  and  understood,  the  lantern  ma}' 
be  more  conveniently  analyzed  for  troubles  when  something  goes 
wrong,  its  total  adjustment  may  be  more  quickly  attained  and  main- 
tained, in  short,  better  work  can  be  done,  by  considering  the  con- 
denser as  related  to  the  lens,  not  to  the  slide,  and  in  considering  the 
condenser  as  a  part  of  the  lens  itself,  as  indeed  it  is.  Consider  the 
lens  system  as  consisting  of  all  the  glasses  through  which  the  light 
passes  on  its  way  from  the  arc  lamp  to  the  picture  screen,  and  con- 
sider that  the  slide  to  be  projected  is  inserted  into  tliis  complete 
system  between  two  component  parts  of  the  lens  system. 

Condenser  a  Part  of  the  Lens.  Unless  the  operator  gets  the 
mental  conception  that  his  condenser  is  a  part  of  his  lens,  he  is  likely 
to  overlook  the  fact  that  for  good  pictures  his  condensers  must  be 
focused  into  his  lens,  believing  it  sufficient  that  his  lens  is  focused 
upon  the  picture  slide. 

Clip  an  illustration  from  a  magazine  or  newspaper,  moisten  and  rub  off 
the  printing  from  the  back  of  the  clipping,  if  printed  on  the  back,  and  put 
this  clipping  into  the  lamphouse,  the  picture  side  against  the  glass  surface  of 
the  back  condenser.  The  stereo  lens  may  be  adjusted  to  focus  the  picture 
upon  the  screen.  With  accurate  condensers  the  image  on  the  picture  screen 
would  be  sharp,  but  with  cheap  condensers  it  will  be  much  distorted  and 
blurred  in  some  places. 

This  simple  experiment,  however,  will  show  that  the  condensers  are 
a  part  of  the  lens  systems  of  Figs.  19,  20,  and  21,  and  as  much  as 
they  are  in  the  systems  of  Figs.  17  and  18. 

Plano=Convex  Condensers  in  Pairs.  Three  forms  of  condensers 
are  shown  in  Figs.  19,  20,  and  21 — the  meniscus  in  Fig.  19,  the  convex 
in  Fig.  20,  and  the  plano-convex  in  Fig.  21.  In  each  of  these  systems, 
the  condenser  is  shown  as  tin-owing  into  the  lens  all  of  the  light  which 
it  catches  from  the  lamp.  The  more  light  which  the  condenser  can 
catch  from  a  lamp  of  a  standard  of  brightness,  the  more  light  will 
the  lens  and,  therefore,  the  picture  screen  receive  and,  therefore, 
the  more  desirable  does  the  particular  form  of  condenser  become. 
The  plano-convex  condenser — probably  because  it  presents  a  flat 
face  to  the  lamp — has  the  power  of  picking  up  more  rays  of  light  and 
of  standing  the  heat  of  the  lamp  \\ithout  breaking  better  than  any 
other  form  of  condenser  of  equal  price. 


28 


I 


OPTICAL  LANTERN 


19 


The  plano-convex  condensers  are  used  in  pairs,  the  first  of  the 
pair,  that  nearest  the  lamp,  having  the  function  of  bending  the  rays 
into  parallelism ;  then  they  pass  to  the  second  condenser  which  bends 
them  again  and  throws  them  into  the  glasses  of  the  objective  lens. 

Focal  Lengths.  The  theoretical  requirement  of  the  condenser 
glasses  in  bending  the  rays  involves  glasses  of  different  focal  lengths 


Fig.  20.     Development  of  the  Modem  Type 
of  Condenser  (Double   Convex  Condenser) 

to  attain  the  condition  of  adjustment  in  which  they  will  give  the  most 
effective  results.  For  theater  projection,  both  for  stereo  or  lantern- 
slide  projection,  and  for  motion-picture  projection,  this  requirement 
involves  the  use  of  a  glass  at  C-1  nearer  the  lamp.  Fig.  21,  of  shorter 
focal  length  than  the  glass  at  C-2  farther  from  the  lamp,  but  such  is 
not  the  practice.  The  difference  in  the  projected  picture  upon  the 
screen  is  slight,  and  the  convenience  of  using  both  glasses  alike  is  so 
great  in  comparison  that  the  custom  of  most  operators  is  to  use  two 
glasses  of  the  same  focal  length.  In  this  use,  the  first  lens  does  not 
bend  the  rays  quite  as  much  as  it  should,  and  they  are  still  slightly 
divergent  between  the  condenser  glasses,  resulting  in  the  loss  of  some 


Fig.  21.     Development  of  the  Modern  Type  of 
Condenser  {.Present  Condenser  System) 

light  around  the  edge  of  the  second  glass,  with  consequent  slight  lack 
of  brilliancy  in  the  picture  upon  the  screen. 

Theory  makes  the  condenser  glass  C-1  of  Fig.  21  about  six  inches 
focal  length,  and  the  condenser  glass  C-2  of  that  figure  about  two 
inches  longer  than  the  focal  length  of  the  stereo  lens  L.  Two  sixes 
is  the  usual  combination  for  service.  The  condenser  has  the  peculiar 
feature  that  any  length  of  condenser  glasses  will  make  some  sort  of 


29 


20  THE  MOTION  PICTURE 

projection.  The  operator  who  reahzes  tliat  his  condenser  is  a  part 
of  his  lens  will  im>prove  his  projection  by  bringing  the  two  into  har- 
mony as  far  as  possible. 

Projecting  machines  are  equipped  with  condensers  by  the 
manufacturers  and  are  shipped  with  fixed  distances  between  con- 
densers and  motion  head  without  reference  to  the  focal  length  of 
the  leqs  to  be  used  in  the  motion  head,  and  the  focal  length  of  the 
condenser  is  not  regulated  to  the  length  of  the  stereo  or  lantern- 
slide  lens  nor  with  reference  to  the  focal  length  or  position  of  the 
optical  center  of  the  motion-head  lens,  since  neither  is  known  at  the 
factory,  the  size  of  screen  and  the  length  of  throw  from  the  project- 
ing station  to  the  picture  screen  being  unlsjiown.  If  the  condenser 
lengths  are  inaccurate,  the  optical  system  as  a  whole  may  be  cor- 
rected by  determining  the  proper  position  of  the  lamp  to  bring  the 
rays  bent  by  the  condensers  to  cross  at  the  optical  center  of  the  lens, 
the  optical  center  of  the  lens  being  previously  determined  by  focusing 
a  slide  upon  the  screen. 

Adjustment  fcr  Slides  or  Motion  Head.  In  a  lantern  having 
stereo  lens  and  motion  head,  the  distance  from  the  condensers  to  the 
optical  center  of  the  stereo  lens  may  be  different  (probably  is  different) 
from  the  distance  between  the  condensers  and  the  optical  center  of 
the  motion-head  lens.  This  condition  requires  that  for  good  pictures 
the  position  of  the  lamp  in  the  lamphouse  must  be  changed  each 
time  the  lamphouse  is  moved  from  motion  head  to  stereo  lens,  or 
vice  versd.  The  proper  adjustment,  when  once  learned,  may  be 
attained  by  noting  the  size  and  the  shape  of  the  s}X)t  of  light  around 
the  film  window  of  the  motion  head,  or  upon  the  edges  or  light  guard 
of  the  stereo  lens. 

Emergency  Projection.  With  reference  to  condensers,  emergency 
projection  means  projection  when  there  are  no  condensers  available. 
A  cracked  condenser  is  serviceable  as  long  as  it  holds  together — it 
is  better  than  hone.  With  the  motion  head,  either  or  both  condensers 
may  be  cracked,  and  the  picture  on  the  screen  will  not  show  it.  AVith 
the  lantern  slide  and  the  stereo  lens,  the  back  condenser  will  show 
its  cracks  less  than  the  front  condenser,  but  any  crack  in  the  front 
glass  will  show  plainly  upon  the  screen.  It  is  when  the  condenser 
glass  falls  to  pieces  and  drops  out  of  the  cell  that  the  operator  is 
required  to  ado])t  emergency  methods  to  save  the  show. 


30 


OPTICAL  LANTERN  21 

With  one  condenser  gone,  put  the  remaining  condenser  in  the 
front  position — the  C-2  position  of  Fig.  21 — and  move  the  lamp  back 
in  the  lamphouse  until  the  rays  after  passing  through  the  condenser 
cross  at  the  optical  center  of  the  lens;  if  the  lamp  cannot  be  moved 
so  far,  move  it  as  far  as  possible.  The  picture  upon  the  screen 
will  be  of  tlie  usual  size,  but  of  much  less  than  usual  brilliancy.  If 
the  edges  are  dim,  and  a  longer  lens  is  available,  use  the  longer  lens, 
thus  reducing  the  size  of  the  picture  and  increasing  its  brilliancy. 

In  the  nftotion  head,  the  stereo  lejis  even  may  be  moved  to  a 
position  in  front  of  the  motion  head  and  the  regular  motion-head 
lens  removed,  projecting  the  motion  pictures  through  the  stereo 
lens.  The  resulting  picture  upon  the  screen  (taking  the  usual  run 
of  motion  theaters)  would  be  about  four  feet  wide  by  three  feet  high, 
but  bright,  sharp,  and  distinct  with  the  one  condenser. 

Diffusion  Projection.  With  both  condensers  lost,  use  ground 
glass  instead — four  sheets,  two  with  the  smooth  sides  together  for 
the  back  condenser  and  two  with  the  smooth  sides  together  for  the 
front  condenser.  They  are  diffusers  rather  than  condensers,  but 
they  will  give  upon  the  screen  a  picture  of  full  size  but  lacking  in 
brilliancy  if  the  usual  objective  lenses  are  retained.  The  longest 
available  lenses  should  be  used,  sacrificing  something  in  size  and 
gaining  something  in  brilliancy. 

Adjustment  of  the  Optical  System.  Select  the  motion-head 
lens  for  foeal  length  according  to  the  lens  table,  selecting  it  for  the 
length  of  throw  from  the  lens  to  the  picture  screen  and  for  the  size 
of  picture  desired  upon  the  screen. 

Place  a  piece  of  film  or  a  piece  of  scratched  mica  in  the  film 
window  and  focus  it  upon  the  screen.  The  lens  being  a  double  lens, 
?.  e.,alens  tube  having  glasses  at  both  ends,  it  may  be  taken  that  the 
optical  center  of  the  lens  is  at  the  center  of  the  tube 

The  length  of  focus  of  the  front  condenser  glass,  C-2  of  Fig.  21, 
should  be  equal  to  the  distance  from  the  focal  center  of  the  motion- 
head  lens  to  a  point  midway  between  the  two  condenser  glasses.  It 
may  be  less,  rather  than  more. 

The  length  of  the  focus  of  the  back  condenser  glass — C-1  of  Fig. 
21 — should  be  about  six  inches.  A  longer  length  of  focus  will  reduce 
the  breakage  due  to  the  heat  of  the  lamp,  while  a  shorter  length 
of  focus   will   give  a  brighter   light   upon  the  screen  but  probably 


31 


22  THE  MOTION  PICTURE 

with  greater  breakage,  because  the  himp  will  be  brought  nearer  to 
the  glass. 

Push  the  lamphouse  away  from  the  motion  head  so  that  the  cone 
of  light  will  pass  at  the  side  of  the  motion  head;  then  adjust  the 
lamp  until  the  cone  of  light  "crosses"  just  at  the  side  of  the  motion- 
head  lens  and  opposite  the  focal  center  of  the  lens.  The  point  where 
the  cone  of  light  crosses  is  the  point  where  the  solid  beam  of  light 
coming  from  the  condensers  reaches  its  smallest  diameter  and  then 
begins  to  spread  toward  the  picture  screen.  As  the  lamp  is  moved 
forward  in  the  lamphouse,  this  point  of  crossing  moves  forward 
away  from  the  condensers  and  toward  the  picture  screen.  As  the 
lamp  is  moved  back  in  the  lamphouse,  the  point  of  crossing  is  drawn 
back  toward  the  condensers.  Stop  it  opposite  the  focal  center  of 
the  motion-head  lens.  Then  draw  the  lamphouse  back  to  the 
motion-head  and  notice  the  appearance  of  the  circle  of  light  about 
the  film  window. 

The  appearance  of  the  circle  of  light  around  the  film  window 
when  the  lamp  ancl  the  optical  system  are  in  proper  adjustment 
should  be  remembered  by  the  operator  as  a  standard.  Before  open- 
ing the  film-window  shutter  to  begin  projection,  the  circle  of  light 
may  be  brought  to  that  standard  as  nearly  as  the  operator  can  remem- 
ber it  and  little  or  no  adjustment  Avill  be  required  to  improve  the 
projected  picture  after  the  film  window  is  opened. 

The  optical  system  having  been  adjusted  to  the  requirements 
of  the  motion  head  in  preference  to  the  requirements  of  the  fixed  slide 
and  stereo  lens,  the  process  may  be  repeated  for  the  stereo  lens. 

Select  the  stereo  lens  for  focal  length  according  to  the  lens  table, 
selecting  for  length  of  throw  and  size  of  picture  desired.  To  produce 
a  picture  of  comparative  size,  the  length  of  the  stereo  lens  will  be 
about  three  times  that  of  the  motion-head  lens. 

Place  a  slide  in  the  carrier  and  focus  the  slide  upon  the  screen. 
The  lens  being  a  double  lens,  it  may  be  taken  again  that  the  optical 
center  is  at  the  center  of  the  tube. 

Draw  the  lamphouse  to  one  side  and  again  adjust  the  lamp  to 
cause  the  cone  of  light  to  cross  at  the  center  of  the  stereo  lens.  Notice 
the  appearance  of  the  circle  of  light,  or  of  the  cone  of  rays  as  it  enters 
the  stereo  lens.  This  appearance  may  be  remembered  and  will  help  in 
making  a  proper  adjustment  quickly  for  the  projection  of  lantern  slides. 


82 


OPTICAL  LANTERN  23 

The  cone  of  light  usually  is  visible  in  the  room  by  reason  of  the 
dust  motes  floating  in  the  air.  If  it  is  not  visible  for  this  cause,  its 
formation  may  be  studied  and  the  point  of  crossing  may  be  deter- 
mined by  holding  a  white  card  in  the  cone  of  light  and  moving  it 
toward  and  from  the  condenser  until  the  circle  of  light  upon  the 
card  is  at  its  smallest,  which  will  be  the  point  of  crossing. 

It  is  a  great  convenience  in  changing  from  motion-head  to  stereo 
lens  if  they  can  be  so  placed  that  readjustment  of  the  lamp  in  the 
lamphouse  will  not  be  required.  This  can  be  accomplished  by 
moving  the  motion  head  toward  or  from  the  lamphouse  to  bring  the 
focal  center  of  the  motion-head  lens  opposite  the  focal  center  of  the 
stereo  lens. 

A  lamp  adjustment  taken  by  many  operators  is  that  lamp  posi- 
tion in  which  the  circle  of  light  upon  the  film  window  is  reduced  to 
the  smallest  circle  possible  which  will  fill  the  window.  This  results 
in  a  brighter  picture  upon  the  screen  in  spots,  but  the  distribution 
ujion  the  screen  may  be  irregular  in  intensity  and  objectionable 
coloring  is  likely. 

THE  SLIDE  CARRIER 

Just  in  front  of  the  condensers  is  placed  a  frame  for  holding  the 
picture  slide.  A  part  of  the  frame  is  made  to  slide,  and  is  provided 
with  windows  and  grooves  for  two  picture  slides.  The  movable 
part  of  the  frame  is  arranged  with  stops  at  both  ends  of  its  travel  so 
that  it  will  stop  with  one  or  the  other  of  its  two  picture  slides  in  proper 
position  for  projection  by  the  lamp  and  lenses  upon  the  picture 
screen,  the  other  picture  slide  being  at  that  time  out  of  the  light  of 
the  lantern,  waiting  for  the  frame  to  be  pushed  across  into  its  other 
position  to  bring  the  waiting  slide  into  proper  position  for  projection. 
The  second  slide  being  thus  brought  into  the  light  of  the  lantern, 
the  first  slide  is  removed  from  the  carrier  and  the  third  slide  is  put  in 
its  place.  The  carrier  then  is  pushed  back  into  its  first  position, 
showing  the  third  slide  upon  the  screen,  and  so  on,  the  slides  being 
placed  in  the  carrier  first  at  the  right  and  then  at  the  left,  the  carrier 
changing  ends  for  each  change  of  picture  upon  the  picture  screen. 

Simple  Form  of  Carrier.  The  simple  form  of  slide  carrier  is 
shown  in  the  illustration  of  Fig.  22.  The  fixed  frame  comprises  a 
track  across  the  bottom  and  an  open  frame  at  the  middle  of  the  track. 


33 


24 


THE  MOTION  PICTURE 


Within  the  frame  is  shown  the  shde  carrier  with  its  two  windows, 
the  carrier  being  shown  shghtly  out  of  center. 

The  carrier  has  grooves  open  at  the  top  into  which  the  picture 
sUdes  are  shpped  when  they  are  to  be  projected.  Some  carriers 
have  a  single  groove,  four  inches  wide,  admitting   the  American 


Fig.   22.     Simple  Slide  Carrier 

standard  size  of  slide,  which  is  31  X  4;  in  this  type  of  slide  carrier  it  is 
necessary  to  center  carefully  a  foreign  slide  measuring  only  3^  X  3^ 
that  it  may  appear  centered  upon  the  screen  when  the  slide  carrier 
is  pushed  over.  The  picture  of  the  American  slide  is  the  same  size 
as  that  of  the  foreign  slide,  the  additional  area  being  blank  margin. 

Carriers  for  American  and  Foreign  Slides.  Slide  carriers  for 
exhibiting  both  the  American  and  the  foreign  sizes  of  slides  may 
have  a  pair  of  centering  springs  which  push  either  size  to  the  center 
of  the  window,  or  may  have  two  grooves — one  wide  for  the  American 
slide  and  one  narrow  for  the  foreign  slide;  in  the  latter  case,  in  show- 
ing a  mixed  set  of  slides  it  is  necessary  to  change  the  focus  atljustinent 
of  the  stereo  lens  each  time  the  slide  changes  from  one  groove  to  the 
other. 

Slide  Window  Masks.  In  Fig.  23  is  shown  a  masked  slide  win- 
dow.    No  matter  what  the  size  of  the  slide  placed  in  the  carrier,  only 


Fig.   23.     Slide  Holder  Window  Mask 


so  much  f)f  its  picture  will  be  shown  uj)on  the  picture  screen  as  may 
be  seen  through  the  mask  (shown  as  a  black  frame)  in  the  slide 
window. 


34 


OPTICAL  LANTERN 


25 


The  slide-window  mask  is  a  boon  to  the  operator  who  cannot 
make  his  lens  cover  his  slide.  Just  put  in  a  mask  that  the  lens  will 
cover.  The  average  set  of  song  slides  will  be  more  pleasing  with 
the  edges  trimmed  away  by  the  sharp  cut  of  the  slide-window  mask 
than  with  the  corners  trimmed  away  by  fading  first  into  color  and 
then  into  darkness  by  reason  of  the  failure  of  the  lens  to  cover  the 
field. 

Slide=Window  Shutters.  When  the  view  upon  the  screen  is 
changed  merely  by  pushing  the  carrier  across,  the  old  view  races 
off  of  the  screen  at  a  high  speed  and  the  new  view  races  on.  This 
is  considered  objectionable  by  some  people,  although  it  is  a  matter 
of  opinion  whether  some  of  the  cures  are  not  worse  than  the  malady. 

To  cap  the  lens  or  to  operate  a  small  manual  shutter  or  even  a 
pedal  shutter  while  moving  the  slide  across  is  the  simplest  remedy. 
Devices  are  offered  in  connection  with  complicated  slide  carriers 
by  which  the  slide  window  is  closed  by  an  automatic  shutter  except 


Fig.   24.     Slip  Slide  Carrier 

when  the  carrier  is  in  one  or  the  other  of  its  end  positions.  By  push- 
ing the  carrier  across  quickly,  the  interval  of  darkness  caused  by 
the  shutter  becomes  very  brief.  The  interval  of  darkness,  no  matter 
how  brief,  is  objectionable,  as  the  pupils  of  the  eyes  in  the  audience 
begin  to  expand  and  again  must  contract  for  the  succeeding  picture, 
repeating  this  at  every  change. 

Slip  Slide  Carrier.  Li  the  slip  slide  carrier,  shown  in  Fig.  24, 
the  slide  at  the  right  is  in  the  window  for  projection  and  the  slide 
at  the  left  is  the  new  slide  next  to  be  projected.  The  lever  and  knob 
at  the  left  engage  the  new  slide  and  push  it  into  a  position  in  front  of 
the  slide  already  on  the  screen.  Thus  both  slides  are  thrown  upon 
the  screen  in  confusion  for  an  instant.  The  pawls  of  the  con- 
trolling handle  are  released  from  the  new  slide  when  it  reaches  its 
position  for  projection  and  engage  the  old  slide  to  withdraw  it,  so 


35 


26  THE  MOTION  PICTURE 

that  by  the  return  of  the  operating  handle  the  old  slide  is  withdrawn, 
leaving  the  new  one  in  position  in  the  beam  of  light.  As  the  old 
slide  is  drawn  from  under  the  new  one,  a  set  of  springs  presses  the 
new  slide  down  into  the  position  formerly  occupied  by  the  old  slide, 
that  is,  into  the  position  of  proper  focus  for  the  lens.  The  change 
of  slides  can  be  made  very  quickly.  A  modification  of  this  device 
carries  an  opaque  shutter  which  closes  the  slide  window  as  the  new 
slide  comes  in  and  opens  it  as  the  old  slide  is  drawn  out,  thus  avoid- 
ing the  confusion  of  projecting  both  slides  at  once. 

Mechanical  Slide  Changers.  Mechanical  changers  take  two 
forms,  which  may  be  classified  as  semi-automatic  and  full  automatic. 
In  the  semi-automatic  type  of  changer,  the  object  desired  is  to  have 
the  view  changed  at  the  desired  instant.  This  is  of  value  in  lectures, 
and  in  illustrated  songs  as  well.  Such  a  device  consists  of  a  spring 
for  drawing  the  carrier  across,  with  a  lever  for  setting  the  spring  to 
tension,  and  an  electromagnet  for  releasing  the  carrier.  The  operator 
in  the  projection  room  places  the  new  slide  in  the  carrier  and  sets 
the  spring  to  tension  to  draw  the  carrier  across.  When  the  lecturer 
desires  to  have  the  new  slide  projected  he  touches  a  push  button  or 
electric  switch  which  releases  the  slide  and  the  spring  draws  it  across. 
The  operator  at  the  lantern  then  replaces  the  old  slide  with  the  next 
of  the  series,  sets  the  spring  to  draw  the  carrier  back,  and  again 
waits  until  the  lecturer  has  released  the  carrier  electrically.  In  the 
case  of  the  illustrated  song,  the  stage  director,  the  orchestra  leader, 
or  the  pianist  would  change  the  slides  by  the  push  button. 

For  the  dissolving  lantern  the  operator  changes  the  slide  in  the 
dead  lantern  and  sets  the  dissolving  shutter  to  tension.  The  con- 
trol exercised  electrically  by  the  lecturer  or  musician  then  releases 
the  dissolving  shutter  to  change  quickly  to  its  other  position,  making 
the  quick  shift  from  slide  to  sliae. 

In  the  full  automatic  changer,  the  slides  are  placed  in  a  rack 
containing  a  space  for  each  slide,  and  this  rack  or  multiple  carrier 
is  stepped  forward,  step  by  step,  either  under  control  of  the  projec- 
tion operator,  the  stage  director,  or  a  musician  in  the  orchestra. 
The  rack  for  holding  the  slides  in  the  full  automatic  changer  takes 
the  form  of  a  wheel  with  the  slides  on  the  edge,  a  chain  with  the 
slides  in  the  links,  or  of  a  nest  of  carriers  in  which  slide  after  slide 
is  brought  into  an  operating  position  and  then  forced  into  position 


36 


OPTICAL  LANTERN 


27 


in  the  beam  of  light  for  projection.  Full  automatic  changers  are 
much  used  in  windows  and  in  pubhc  places  for  the  projection  of 
advertising  slides,  the  changes  being  controlled  by  clockwork. 

Storage  of  Slides.  Sets  of  song  slides  come  packed  in  small 
wooden  boxes,  and  between  repetitions  of  the  song  they  lie  stacked 
upon  the  operator's  table,  lying  close  upon  each  other,  with  no  oppor- 
tunity to  lose  the  heat  of  the  lamp  acquired  while  being  projected, 
and  getting  hotter  every  time  the  set  is  run  through  the  lantern. 
Occasionally  one  or  more  are  knocked  from  the  table  and  the  set 
is  run  a  slide  or  two  short  there- 
after, either  the  operator  or  the 
theater  manager  paying  for  the 
breakage.  A  slide  storage-box 
like  that  shown  in  Fig.  25,  but 
preferably  with  the  hinges  taken 
from  the  lid  so  that  the  lid  may 
be  removed  completely  while 
operating  but  replaced  when 
desired,  will  keep  the  slides  in 
order,  prevent  accidental  bceak- 
age,  prevent   the  insertion  of  a 

slide  in  the  carrier  in  reversed  or  inverted  position,  and  give  the 
slides  a  chance  to  cool  between  successive  projections.  The  an- 
nouncement slides  are  kept  in  one  end,  the  song  slides  in  the 
other.  The  cost  of  one  good  slide  or  two  cheap  slides  is  about  the 
price  of  such  a  box. 

DISSOLVING  LANTERNS 

Up  to  the  time  of  the  introduction  of  the  motion  picture,  the 
dissolving  lantern  was  the  most  interesting  of  all  optical  illusions, 
and  a  favorite  means  of  entertainment.  It  was  developed  to  such 
refinement  of  detail  that  motion  in  projected  pictures  was  well  simu- 
lated in  many  instances.  Entire  scenes  were  played  through  with  the 
very  complete  sets  of  lantern  slides  made  and  used  with  multiple 
lanterns,  some  sets  of  pictures  requiring  four  or  six  lanterns  working 
simultaneously  upon  the  screen  to  produce  the  effects  as  planned. 

Triple  Lantern.  In  Fig.  26  is  reproduced  an  illustration  taken 
from  an  old  book  upon  the  subject  of  the  optical  lantern.     It  shows 


Fig.   25.     Slide  Storage  Box 


37 


28 


THE  MOTION  PICTURE 


a  triple  lantern,  three  lanterns  built  in  one,  with  tubes  and  dissolving 
valves  at  thje  back  for  the  oxv-hydrogen  or  lime  light.  It  was  with 
such  lanterns  as  this  that  truly  "dissolving"  effects  were  produced. 
Imagine  a  rural  scene,  showing  woodland,  meadow,  and  lake. 
It  is  winter,  and  winter  with  a  single  lantern,  winter  with  a  single 
slide.     By  an  auxiliary  slide,  in  the  same  lantern,  skaters  appear 


Fig.   26.     Triple  Lantern  for  Dissolving  Projection 

and  glide  over  the  surface  of  the  little  lake.  The  skaters  pass  off 
the  side  of  the  picture  and  the  scene  again  is  still,  with  a  single  lan- 
tern. Now  the  picture  begins  to  darken;  soon  only  patches  of  snow 
are  left  here  and  there.  The  view  has  been  dissolved  from  the 
first  lantern  used  to  another  lantern  Avith  a  slide  similar  and  register- 
ing exactly  but  with  less  snow.  Two  or  three  or  more  successive 
slides  are  dissolved  each  into  the  next  of  the  set  before  the  snow  is 
entirely  gone  and  the  view  remains  in  the  neutral  colors  of  March, 


38 


OPTICAL  LANTERN  29 

but  with,  yes,  at  first  it  seems  elusive,  but  surely  there  is  a  suggestion 
of  green  in  the  meadow,  positively  now,  and  the  darker  green  of  the 
meadow  is  supplemented  by  a  lighter  green  in  the  treetops.  The 
branches  begin  to  lose  themselves  in  the  mass  of  growing  foliage, 
all  in  full  color,  and  summer  is  here.  How  many  slides  have  been 
used  in  the  change  is  known  only  to  the  men  behind  the  machines 
at  the  projection  station;  the  audience,  apparently,  has  seen  but 
one  lantern  slide,  but  one  view,  in  which  not  a  tree  nor  house  nor 
post  of  fence  has  moved,  yet  a  view  which  has  changed  before  their 
eyes  in  a  manner  even  more  wonderful  than  the  changing  of  the 
modern  motion  picture,  whose  flicker  betrays  at  once  its  mechanism 
and  its  origin. 

In  the  summer  scene  (from  one  lantern)  the  lake  is  no  longer 
ice  and  a  white  swan  (from  a  second  lantern)  glides  upon  its  surface. 
Clouds  begin  to  appear  in  the  sky  (dissolving  the  view  from  the  first 
lantern  into  a  third  lantern  while  the  second  lantern  holds  the  swans 
moving  upon  the  lake).  The  swan  disappears  and  lightning  begins 
to  flash  (from  the  swan's  lantern),  the  rain  begins  to  fall  (view  from 
the  third  lantern,  rain  from  the  first  lantern,  lightning  from  the  second 
lantern),  the  clouds  move  across  the  sky  (mechanical  attachment 
for  the  third  lantern),  and  the  storm  rages,  as  with  the  modern  motion- 
picture  film,  sheet-iron  thunder,  bean-bag  rain,  and  wind  drum, 
complete. 

The  lightning  ceases,  lights  appear  in  the  windows  of  a  house; 
presently  the  rain  ceases  and  the  clouds  begin  to  break,  and  by  and 
by  the  view  dissolves  into  a  moonlight  scene  with  drifting  clouds, 
ultimately  giving  a  clear  sky,  moonlight  sparkling  on  the  surface  of 
the  lake,  etc. 

A  notable  set  of  slides  showed  the  burning  of  a  building,  the 
breaking  out  of  the  fire,  the  arrival  of  the  fire  brigade,  etc. 

From  this  origin  and  from  this  field  of  activity  comes  the  dis- 
solving lantern  of  the  song  slide  set,  where  its  duty  now  remains 
solely  to  shift  from  one  slide  to  some  other  probably  quite  unlike  it, 
the  dissolving  function  of  the  lantern  being  operative  merely  to  save 
the  eye  of  the  spectator  from  the  shock  of  other  methods  of  change. 

The  Double  Lantern.  The  modern  dissolving  lantern  consists 
of  two  lamphouses,  most  conveniently  mounted  one  above  the  other, 
although  the  arrangement  of  having  them  side  by  side  has  been 


39 


30 


THE  MOTION  PICTURE 


tried.  Each  lamphouse  is  equipped  with  lamp,  condenser,  and 
lens  system,  slide  carrier,  and  a  shutter.  The  two  shutters  of  the 
two  lanterns  are  operated  by  a  single  handle  and  are  so  arranged 
that  as  the  handle  is  moved  one  shutter  is  gradually  closed  and  the 


Fipr.  27.     Comliiiiation  Projector,  for  Motion  and  Fixed  Pictures,  with 
Single  Lantern 

other  gradually  opened.  If  in  connection  with  a  motion  head, 
the  lower  lamphouse  is  arranged  to  slide  for  the  stereo  lens  or  for  the 
motion  head,  the  upper  lamphouse  being  fixed  in  position.  Slides 
are  projected  successively  by  placing  the  first  slide  in  the  lower  carrier, 
the  second  in  the  uj)pcr.     The  first  projection  is  made  from  the  lower 


40 


OPTICAL  LANTERN 


31 


lantern,  the  handle  is  shifted  to  change  the  shutters,  the  slide  is  changed 
in  the  lower  lantern  and  the  handle  again  is  moved  to  change  the 
shutters,  when  the  slide  in  the  upper  carrier  is  changed.  The  slide 
carriers  in  such  lanterns  may  be  of  simpler  or  more  convenient 
form  than  in  the  single  lantern.  The  pictures  projected  by  the  two 
dissolving  lanterns  should  be  of  the  same  size  and  carefully  lined  up 


28.     Combination  Projector,  for  Motion  and  Fixed 
Pictures,  witli  Double  Dissolving  Lantern 

together  upon  the  screen.  Modern  single  and  double  lanterns  for 
motion  head  and  dissolving  slides  are  shown  in  Fig.  27  and  Fig.  28. 
Lining  Up  the  Double  Lantern.  In  setting  up  the  projecting 
lantern  with  motion  head,  care  should  be  taken  to  bring  the  two 
pictures   into   approximately   the    same  position  upon    the  screen. 


41 


32  THE  MOTION  PICTURE 

although  the  pictures  from  the  motion  head  and  from  the  stereo  lens 
will  be  of  different  shape  and  may  be  widely  different  in  size  unless 
the  lenses  are  carefully  matched.  In  setting  up  the  dissolving 
lantern  the  two  pictures  from  the  lanterns  should  coincide  just  as 
accurately  as  it  is  possible  for  the  operator  to  make  them.  Adjust- 
ment screws  will  be  found  on  the  upper  lantern  for  this  purpose. 

Alignment  Masks.  Considering  the  inaccuracy  of  slide  masks 
in  commercial  sets  of  song  slides,  it  is  impossible  to  secure  perfectly 
the  desired  result  in  dissolving  without  slide-window  masks,  such  as 
shown  in  Fig.  23.  With  two  such  masks,  cut  from  thin,  ferrotype 
iron,  or  any  thin  sheet  metal,  of  the  same  size  and  shape,  and  with 
two  stereo  lenses  matched  to  exactly  the  same  focal  length  (the  lens 
makers  will  sell  two  matched  lenses  for  an  extra  charge  for  match- 
ing), it  is  possible  to  dissolve  without  slides  from  one  lantern  to  the 
other  without  showing  any  change  in  the  edges  of  the  white  field  of 
the  screen.  With  this  arrangement,  good  effects  will  be  obtained 
with  dissolving  slides  which  are  large  enough  to  fill  the  windows. 

Dissolving  Shutters.  The  dissolving  shutters  should  be  set  to 
close  each  lens  half  when  the  lever  is  in  the  middle  of  its  travel. 
The  light  should  be  cut  off  just  in  front  of  the  lens,  near  the  lens, 
preferably  with  a  shutter  having  a  saw-tooth  edge  operating  from 
one  side  with  a  horizontal  movement  across  to  the  other  side.  The 
shutters,  having  two  wings  which  cut  oif  the  edges  of  the  lens  first, 
leaving  the  middle  of  the  lens  effective  until  the  last,  and  also  the 
iris  shutters  which  work  between  the  lens  glasses,  inside  the  lens 
tube,  and  shut  off  the  light  beginning  with  the  outer  edges  and 
gradually  narrowing  it  down  to  a  smaller  opening  in  the  middle  of 
the  lens  until  finally  the  light  is  stopped  altogether,  are  fallacious  in 
theory,  for  this  reason:  By  such  shutters,  the  volume  of  the  light  is 
reduced  but  the  definition  of  the  fainter  image  upon  the  screen  is 
increased.  With  the  shutter  two-thirds  over,  the  new  image  has 
twice  the  brilliancy,  but  the  old  image  has  greater  definition — an 
objectionable  feature.  In  the  simpler  cut-off  working  from  one 
side  only,  the  definition  is  impaired  as  the  volume  of  light  is  dimin- 
ished and  the  vanisliing  })icture  fades  away  in  a  blur  which  the  eye 
caiuiot  follow,  the  eye  acting  to  pick  up  the  new  picture  as  soon  as 
that  picture  has  the  greater  light  volume,  it  having  also  from  that 
time  the  greater  sharpness  of  definition  as  well. 


42 


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OPTICAL  LANTERN  33 

Equipment  of  the  Second  Lantern.  The  second  lantern,  or  upper 
lantern  of  the  double  lantern,  should  be  complete  and  as  far  as  pos- 
sible separate  from  the  lower  lantern.  Positively  it  must  have  a 
rheostat  separate  from  that  of  the  motion-head  lantern,  with  separate 
switch  for  opening  its  electric  leads  and  separate  wiring  from  the 
switch  through  the  rheostat  to  the  lamp.  '  Obviously,  the  lower 
lantern  may  be  called  upon  for  use  in  the  ordinary  way  for  motion 
and  fixed  projection  without  dissolving,  in  case  the  upper  lantern  is 
out  of  order,  or  the  supply  of  carbons  runs  short;  it  is  advisable  also 
to  have  the  upper  lantern  complete  for  similar  use  alone,  removing 
it  from  its  higher  position  to  the  lower.  The  lower  lantern  should 
have  the  double-slide  carrier  which  it  would  require  if  the  upper 
lantern  were  not  used. 

Operation  of  the  Double  Lantern.  With  electric  lamps  in  the 
lanterns,  the  lamps  are  burned  all  the  time  of  dissolving  projection, 
since  the  striking  and  regulating  of  the  arc  requires  too  much  time 
to  be  repeated  for  each  new  slide.  During  the  projection  of  a  roll 
of  film  with  the  motion  head,  the  upper  lantern  may  be  cut  out, 
striking  the  upper  arc  again  while  the  lower  lantern  is  projecting  an 
announcement  slide  or  a  song  title  slide  through  its  stereo  lens. 
The  upper  lantern  requires  the  same  care  as  the  lower,  and  its  con- 
densers should  be  identical  with  those  of  the  lower  lantern,  adjust- 
ing it  to  match  the  lower  lantern  in  every  way.  With  condensers 
of  the  same  focal  length,  the  lamp  must  be  adjusted  to  give  the  same 
appearance  of  the  circle  of  light  upon  the  back  of  the  stereo  lens  tube. 
The  rheostat  of  the  upper  lantern  must  have  the  same  resistance  as 
that  of  the  lower  lantern,  and  should  be  of  the  same  construction  to 
have  the  same  radiating  capacity.  The  same  class  of  carbons  should 
be  used  for  the  two  lanterns,  and  the  carbons  should  be  set  at  the 
same   angle. 

Single=Lantern  Dissolvers.  If  the  perfect  single-lantern  dis- 
solver  has  been  produced,  it  at  least  has  not  come  into  general  use. 
The  object  of  the  single-lantern  dissolver  is  to  fade  the  picture  screen 
from  one  picture  to  another  in  the  manner  in  which  the  double  lantern 
dissolves  a  view  into  a  dissimilar  one  (no  reference  to  the  older  art 
of  dissolving),  the  result  being  accomplished  with  a  single  lamphouse. 
The  slip  slide  carrier  is  a  compromise  effort  in  this  direction. 

A  promising  dissolver  for  single  lanterns  is  arranged  as  follows: 


43 


34  THE  MOTION  PICTURE 

The  slide  carrier  is  moved  forward  from  the  condensers  until  a  separa- 
tion of  about  three  inches  is  attained ;  then  a  forty-five-degree  mirror 
is  mounted  slidably  between  the  condensers  and  the  carrier  to  reflect 
the  beam  of  light  toward  the  ceiling,  a  second  slide  holder  and  second 
objective  lens  are  arranged  in  the  vertical  beam  of  light,  and  a  second 
mirror  is  arranged  above  the  vertical  objective  lens  to  reflect  the  beam 
of  light  toward  the  picture  screen.  The  first  slide  being  projected 
by  the  lower  or  horizontal  lens,  the  second  slide  is  placed  in  the  holder 
of  the  vertical  system  and  the  mirror  is  slid  in  to  transfer  the  beam 
of  light  from  the  slide  of  the  horizontal  to  the  slide  of  the  vertical 
lens  system.  Shutters  are  not  required  for  the  lenses.  This  gives 
the  effect  of  changing  pictures  by  moving  a  vertical  line  across  the 
picture  screen  from  side  to  side,  the  old  picture  disappearing  before 
the  line  and  the  new  picture  appearing  after  the  line. 

A  modification  is  the  substitution  of  a  piece  of  polished  clear 
plate  glass  for  the  mirror,  leaving  it  always  in  its  reflecting  position 
when  projecting  lantern  slides,  whereby  the  light  of  the  lamp  is 
divided  between  the  horizontal  and  the  vertical  lenses  of  the  system. 
With  this  arrangement,  a  pair  of  dissolving  shutters  may  be  used 
and  the  fading  of  the  entire  view  at  once  into  the  next  view  is  obtained 
as  with  the  double  lantern. 

Precautions  in  Dissolving.  With  the  electric  arc  as  a  lamp, 
and  with  both  arcs  burning  all  the  time  during  the  exliibition  of  a 
series  of  views,  the  only  danger  to  the  picture  screen  is  the  projec- 
tion of  ludicrous  combinations  of  two  views,  either  successively 
shown  or  during  the  interval  of  superposition,  when  both  are  upon 
the  screen  together. 

Reversals.  The  slides  must  be  put  into  the  carriers  right  side 
up  (which  is  "head  down"  in  the  carrier),  for  an  inverted  slide  is 
just  as  comical  in  the  dissolving  lantern  as  anywhere  else.  A  "re- 
versed" slide,  however,  may  be  rather  more  comical  in  a  dissolving 
lantern  than  in  a  single  lantern.  By  "reversed"  slide  is  meant  a 
slide  which  is  put  into  the  slide  carrier  "head  down"  but  with  the 
wrong  side  of  the  glass  turned  toward  the  lamp,  reversing  the  picture 
on  the  scn^en  right  for  left.  With  the  same  scene  on  two  successive 
slides,  probably  with  a  change  only  in  the  position  of  the  figures,  as 
frequently  occurs  in  song  slide  sets,  dissolving  one  scene  into  the 
other  with  one  of  the  slides  reversed  produces  the  crazy  effect  of  a 


44 


OPllCAL  LANTERN  35 

prominent  feature  of  the  scenic  setting  disappearing  from  one  side 
of  the  scene  and  appearing  simidtaneously  on  the  other  side,  every 
fixed  detail  of  the  scene  changing  places  similarly,  as  though  the  scene 
were  upon  a  revolving  stage  acting  under  control  of  some  magician's 
wand.  This  is  avoided  easily  by  arranging  the  slides  properly  in 
their  boxes  before  starting  the  series. 

Slide  Alignment.  Where  two  slides  follow  each  other  with  the 
same  scene  setting,  the  slides  apparently  having  been  made  from 
negatives  made  without  changing  the  position  of  the  camera,  it  is 
desirable  to  bring  the  two  views  into  alignment  so  that  the  trees  and 
the  other  fixed  objects  will  not  be  "doubles"  on  the  screen  during 
the  act  of  dissolving.  Knowing  this  particular  feature  of  the  two 
successive  slides,  the  dissolving  shutter  may  be  opened  upon  the 
second  slide  so  slightly  that  the  audience  will  not  note  the  coming 
of  the  new  picture,  yet  the  operator  may  be  able  to  note  some  par- 
ticular visible  detail  and  bring  the  new  picture  into  alignment  with 
the  old  by  moving  the  slide  carrier  of  the  new  slide.  Then  proceed- 
ing with  the  dissolving  shutter  very  slowly,  the  figures  of  the  scene 
alone  changing  slowly  and  the  fixed  objects  remaining  upon  the 
picture  screen  as  though  but  one  slide  were  being  shown,  the  effect 
is  delightful  and  well  worth  the  effort  required  to  attain  it.  It  is  a 
step  toward  bringing  to  life  again  the  old  art  of  the  dissolving  lantern. 

The  operator  who  desires  to  attain  this  effect  and  who  fortunately 
has  a  set  of  slides  with  two  slides  in  it  capable  of  the  effect,  always 
can  secure  the  required  alignment  by  gluing  bits  of  paper,  card,  or 
match  sticks  to  the  top  edge  and  to  the  side  edge  of  one  or  the  other 
of  the  slides,  carefully  bringing  them  into  alignment  upon  the  screen 
before  showing  the  set  before  an  audience.  In  this  case,  the  slide 
arranged  for  the  lower  lantern  in  the  preliminary  alignment  must 
be  projected  from  that  lantern  when  the  effect  is  desired,  for  it  is 
most  unlikely  that  the  two  lanterns  themselves  will  be  so  perfectly 
adjusted  as  to  permit  the  slides  to  be  projected  interchangeably 
from  the  two  carriers  and  get  the  proper  alignment  for  dissolving 
in  both  cases. 

The  utter  extinction  of  the  old  art  of  the  dissolving  lantern  is 
much  regretted.  Slide  makers  as  well  as  lantern  operators  are  to 
blame,  the  makers  either  forgetting  the  subject  altogether,  or  taking 
for  granted  that  the  operators  do  not  know  how  to  dissolve. 


45 


30  THE  IVIOTION  PICTURE 

Many  sets  of  song  slides  show  a  face  in  a  flower,  in  a  bouquet, 
or  in  a  medallion,  or  some  fixed  setting  equivalent  to  a  frame.  A 
slide  showing  the  bouquet  without  the  face,  dissolved  skillfully  into 
a  slide  showing  the  bouquet  or  other  device  with  the  face,  would  please 
the  audience.  Just  for  the  simple  reason  that  it  would  please  the 
audience,  the  theater  manager  would  like  to  have  it  and  the  slide 
maker  should  offer  it.  Sets  of  slides  (plebeian  song  slides)  especially 
made  for  the  dissolving  lantern  (and  the  skillful  operator)  should 
be  offered  by  the  slide  manufacturers.  The  construction  of  such  a 
dissolving  set,  by  slides  additional  to  the  usual  set,  and  made  at  the 
same  time,  and  added  to  the  set  when  used  for  the  dissolving  lan- 
tern, will  add  to  the  interest  of  the  show  and  the  reputation  of  the 
slide  maker;  let  the  theater  manager  demand  them  and  the  demand 
will  be  met  by  the  manufacturers;. 

Speed  of  Change.  The  easiest  method  of  control  which  the 
operator  has  in  a  set  of  slides  is  the  speed  at  which  he  throws  over 
the  dissolving  lever.  This  speed  controls  largely  the  dissolving 
effect  upon  the  screen.  By  carefully  watching  the  matter  of  lever 
speed,  the  change  from  the  old  slide  to  the  new  one  in  many  instances 
may  be  made  pleasing  or  ludicrous. 

Where  the  change  between  the  two  slides  is  in  the  figures  only 
and  the  scene  setting  can  be  brought  int®  alignment,  a  very  slow 
change  produces  a  pretty  effect.  Where  the  change  is  from  a  scenic 
view  to  a  single  object  in  detail,  as  from  a  woodland  scene  to  a  bouquet, 
either  with  or  without  the  usual  framed  face,  the  slow  change  is 
pleasing.  Entirely  dissimilar  views  sometimes  unite  in  unexpected 
combinations  which  are  pleasing  and  which  may  be  offered  to  the 
audience  by  the  slow  movement  of  the  change  lever. 

Entirely  dissimilar  views  sometimes  unite  in  unexpected  com- 
binations which  are  ludicrous  in  the  extreme;  two  moons  in  one  sky, 
or  a  white  horse  and  buggy  upon  a  parlor  sofa,  are  not  connnonly  seen 
except  upon  the  picture  screen  with  a  dissoh  ing  lantern  and  a  thought- 
less operator.  In  a  case  of  this  kind,  make  a  swift  change  by  a  quick 
movement  of  the  dissolving  lever,  or  change  the  order  of  the  slides 
in  the  set.  In  a  lecture,  the  order  of  the  slides  can  not  be  changed. 
In  an  illustrated  song,  the  slides  sometimes  are  so  characterless  and 
so  meaningless,  that  the  rearrangement  of  a  few  of  them,  or  the 
omission  of  a  few  of  them,  is  (juite  permissible. 


46 


OPTICAL  LANTERN  37 

THE  MOTION=HEAD  LANTERN 

The  lantern  is  not  different,  but  its  method  of  operation  has  a 
requirement  additional  to  that  of  a  lantern  used  for  fixed  slide  pro- 
jection only.  The  motion-picture  film  image  being  but  one-tenth 
the  area  of  the  fixed  slide,  and  the  picture  on  the  screen  being  re- 
quired to  be  about  the  same  size,  the  motion-picture  film  must  have 
ten  times  the  intensity  of  light  to  stand  the  increased  magnification. 
An  increase  in  light  intensity  is  effected  by  putting  the  film  in  a  more 
condensed  portion  of  the  cone  of  light  coming  from  the  condensers, 
but  it  remains  a  fact  that  fixed  slide  projection  may  be  accomplished 
satisfactorily  with  a  less  brilliant  arc  than  that  required  for  the  motion 
picture.  To  state  it  the  other  way  about,  the  motion-picture  arc 
must  be  a  hotter  arc  than  that  actually  required  for  fixed  slides, 
and  the  motion-head  lantern  must  furnish  a  stronger  light. 

Having  the  strong  light  for  the  motion  picture,  it  is  easy  to  use 
it  for  the  fixed  slides,  and  it  is  customary  so  to  do.  It  is  customary 
also  to  break  announcement  slides  with  the  excessive  and  unnecessary 
heat.  Take  note  that  the  motion-picture  film  is  exposed  to  the 
heat  of  the  arc  for  about  one-fourteenth  of  one  second,  while  the 
announcement  slide  is  on  the  screen  and  exposed  to  the  heat  of  the 
arc  from  ten  seconds  to  a  full  minute  or  even  more. 

The  motion-head  lantern  equipped  with  an  auxiliary  rheostat, 
or'  with  an  auxiliary'  switch  for  an  adjustable  rheostat,  will  save 
money  by  using  less  electric  current  and  will  save  money  also  by  re- 
quiring fewer  new  announcement  sliders  to  replace  the  slides  broken 
by  the  unnecessary  heat  of  the  motion-head  arc. 

With  direct  current,  fifteen  amperes  is  sufficient  current  for  the 
projection  of  a  fixed  lantern  slide  upon  a  picture  screen  less  than 
fifteen  feet  wide;  for  the  same  screen  the  motion-picture  projection 
should  use  thirty  to  forty  amperes.  With  only  alternating  current 
supplied  from  the  power  mains,  the  currents  used  by  the  lamp  will 
be  greater,  rimning  to  sixty  amperes  for  the  motion-picture  arc, 
but  the  proportion  will  remain. 

Auxiliary  Rheostat.  Two  rheostats  may  be  wired  into  the  same 
lamp  circuit,  the  first  one  of  them  as  usual  and  the  second  one  with 
a  short-circuiting  switch  or  shunting  switch  placed  handy  to  the 
operator  when  standing  at   the  projecting  machine.     The  second 


47 


38 


THE  MOTION  PICTURE 


rheostat  being  shorted  by  the  switch,  the  first  rheostat  is  adjusted 
to  give  the  current  required  for  the  motion-head  arc.  The  shorting 
switch  then  is  opened  and  the  second  rheostat  is  adjusted  (leaving 
the  first  as  it  was)  so  that  the  two  together  give  a  sufficient  current 
for  the  projection  of  lantern  slides,  using  probably  not  more  than 
one-third  and  certainly  not  more  than  one-half  the  current  required 
for  the  motion-head  work.  Thus  adjusted,  the  motion  head  always 
is  pan  with  the  shorting  suatch  closed  and  the  fixed  slides  always  are 
projected  with  the  shorting  switch  open. 

The  arrangement  of  circuits  with  two  rheostats  is  shown  in 
circuit  diagram  in  Fig.  29.  At  the  extreme  left  are  shown  the  street 
mains  of  the  electric  circuit,  appearing  as  two  vertical  lines  SM. 
Branch  wires  pass  from  the  street  mains  to  the  lamp  L  at  the  right 


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Fig.   29.     Connections  for  a  Single  Lantern  with  Two  Rheostats 

and  in  this  pair  of  branch  wires  or  lamp  leads  are  included  first  the 
main  switch  MS  and  then  the  two  rheostats  R  and  AR,  the  auxiliary 
rheostat  AR  being  provided  with  a  shorting  switch  SS  whose  blades 
are  connected  to  the  terminals  of  the  auxiliary^  rheostat.  In  operating, 
the  switch  SS  is  closed  and  the  rheostat  R  is  adjusted  for  the  motion 
arc;  then  SS  is  opened  and  the  second  rheostat  AR  is  adjusted  to  cut 
the  current  down  for  the  song  slides,  fixed  slides  always  being  shown 
with  the  switch  SS  open. 

Auxiliary  Rheostat  for  the  Double  Lantern.  ^Mien  the  doul)le 
lantern  is  used  for  motion  pictures  and  dissolving  slides,  it  will  be 
seen  that  the  upper  lantern  never  is  used  for  the  motion  head.  It 
will  not  require  the  adjustable-current  feature.  A  wiring  diagram 
for  a  double  lantern  for  motion  head  and  di.ssohdng  slides,  equipped 
with  the  current-saving  rheostats,  is  shown  in  Fig.  30. 

At  the  left,  Fig.  30,  the  vertical  pair  of  lines  represents  the  street 
mains  for  the  electric-power  circuit.     From   these  street  mains  a 


48 


OPTICAL  LANTERN 


39 


pair  of  wires  is  taken  to  two  double-pole  knife  switches,  one  switch 
for  each  of  the  two  lanterns.  From  the  lower  knife  switch  the  circuit 
extends  to  the  right  to  the  lamp  of  the  lower  lantern,  passing  through 
the  two  rheostats  R  and  AR,  and  the  shorting  switch  is  connected 
to  the  terminals  of  the  auxiliary  rheostat  AR,  as  it  was  in  Fig.  29. 
With  the  upper  lantern,  however,  it  is  necessary  to  balance  the 
current  against  the  lower  lantern  when  the  shorting  switch  SS  is 
open.  To  show  that  balancing  in  the  diagram,  two  rheostats  are 
shown  in  the  circuit  of  the  upper  lamp,  but  the  shorting  switch  is 
not  required,  as  the  upper  lamp  is  used  for  slides  only.     A  single 


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Fig.   30      Connections  for  a  Dissolving  Lantern  with  Two  Rheostats 

rheostat  will  be  sufficient  for  the  upper  lamp  if  it  is  capable  of  being 
adjusted  to  a  resistance  to  balance  the  two  rheostats  of  the  lower 
lamp. 

Auxiliary  Switch.  Another  arrangement  for  saving  current  and 
condensers  and  also  for  improving  the  quality  of  the  exhibition,  by 
reducing  the  heat  of  the  lamp  for  slides,  is  that  of  using  both  parts 
of  an  adjustable  rheostat  in  the  sense  of  the  two  rheostats  shown 
in  Figs.  29  and  30. 

Fig.  31  shows  an  arrangement  in  a  circuit  diagram  for  a  single 
lantern  using  two  values  of  resistance  from  one  adjustable  rheostat, 
and  Fig.  32  shows  an  arrangement  of  the  same  nature  for  the  double 
or  dissolving  lantern  when  one  of  the  lanterns  is  to  be  used  for  motion 
head  also.  In  Fig.  31,  the  street  mains  are  shown  vertically  at  the 
left;  from  the  street  mains  the  lamp  lead  is  taken  to  the  knife  switch 
on  the  power  board,  and  from  the  knife  switch  through  the  adjustable 


49 


40 


THE  MOTION  PICTURE 


rheostat  to  the  lamphouse  and  lamp.     The  method  of  connecting 
the  rheostat  is  the  one  usually  used,  carrying  the  circuit  to  the  lamp- 


Fig.  31.     Connections  for  an  Adjustable  Rheostat  and  Auxiliary 
Switch  with  a  Single  Lantern 

house  through  all  of  the  wire  of  the  rheostat  and  then  short-circuiting 
as  much  of  the  rheostat  wire  as  is  not  needed.  The  shorting  may  be 
done  in  the  rheostat  either  by  a  movable  handle,  as  indicated  in  Fig. 
31,  or  by  a  short  connecting  wire  between  posts  or  terminals  on  the 


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Fig.   32.     Connections  for  an  Adjustable  Rheostat  and  .\u.xiliary 
Switch  with  a  Dissolving  Lantern 

rheostat.  This  method  of  connecting  a  rheostat  has  the  advantage 
of  giving  a  continuous  circuit  through  all  of  the  wires  of  the  rheostat 
in  case  the  short-circuiting  arm  of  the  device  makes  a  defective  con- 


50 


OPTICAL  LANTERN  41 

tact,  or  in  case  the  short-circuiting  bridging  wire  is  accidentally  broken 
or  disturbed.  Not  only  is  the  projecting  possible  in  case  of  such  an 
accident,  but  there  is  the  further  advantage  that  disastrous  arcing 
will  not  occur  at  the  rheostat  because  the  break  will  be  shunted  by 
the  rheostat  wire.  With  this  method  of  connection  of  the  rheostat 
into  the  lamp  circuit,  either  in  the  case  of  the  arm  type  of  device  or 
of  the  bridging  wire  type,  the  short-circuiting  conductor  of  the  rheo- 
stat is  cut  and  is  taken  by  extension  wires  of  sufficient  size  to  carry 
the  full  current  to  the  short-circuiting  switch  #S»S  which  is  at  the 
operator's  hand  as  he  stands  at  the  j)r()jecting  machine.  By  closing 
the  shorting  switch  SS,  the  coils  of  the  rheostat  are  short-circuited 
and  the  current  has  the  full  value  intended  for  motion-head  work 
according  to  the  adjustment  of  the  rheostat,  but  when  the  shorting 
switch  SS  is  opened,  then  the  rheostat  has  the  short  taken  off  of 
the  coils  which  had  been  cut  out,  and  the  full  resistance  of  the  rheostat 
is  effective  upon  the  lamp  circuit,  cutting  the  current  down  to  a 
proper  amount  suitable  for  use  with  slides  without  endangering  them 
by  excessive  heat. 

The  arrangement  for  the  double  lantern  is  shown  in  circuit 
diagram  in  Fig.  32.  The  lower  lantern  is  equipped  exactly  as  is  the 
lantern  shown  in  diagram  in  Fig.  31,  but  the  upper  lantern  has  the 
full  resistance  value  of  the  rheostat  always  in  its  circuit,  thereby 
equaling  the  adjustment  of  the  lower  lantern  when  the  shorting 
switch  is  open,  no  switch  being  used  with  the  upper  lantern.  Only 
two  rheostats  are  required  for  the  lanterns,  and  they  should  have  the 
same  resistance  that  they  may  balance  each  other  for  the  song  slides 
and  other  dissolving  pictures. 

THE  LENS 

The  projecting  lens  should  bo  anastigmatic,  rectilinear,  and 
achromatic.  It  should  reproduce  upon  the  picture  screen  the  image 
of  the  lantern  slide  with  the  least  possible  degree  of  distortion,  or  with 
a  negligible  amount  of  distortion  of  the  picture. 

Lens  Corrections.  The  usual  lens  for  stereopticon  projection 
is  the  Petzval  type,  an  achromatic,  rectilinear  lens  of  four  glasses, 
the  two  glasses  of  the  front  end  of  the  lens  tube  being  cemented  to- 
gether and  the  two  of  the  back  end  of  the  tube  being  held  apart  by 
a  spacing  ring.     Fig.  33  shows  the  shape  of  the  glasses  used  in  this 


61 


42 


THE  MOTION  PICTURE 


lens.  The  double  end,  with  the  two  glasses  and  the  spacing  ring 
between,  always  should  go  next  to  the  slide,  and  the  single  end  toward 
the  picture  screen. 

With  the  Petzval  lens,  and  with  all  astigmatic  lenses  of  any  type, 
it  is  impossible  to  get  a  sharp  focus  over  all  of  the  picture  screen  at 
the  same  time.  The  peculiarity  of  the  focus  of  the  astigmatic  lens 
is  that  the  picture  sometimes  presents  streaks  radiating  from  a  com- 
mon point  and  at  other  times  presents  large  arcs  around  a  common 
point.  The  focus  seems  to  be  sharp  only  in  a  center  spot  or  in  a 
ring  surrounding  a  center  spot.  In  some  slides  the  defects  of  the 
astigmatism  of  the  lens  can  not  be  noticed,  while  in  others  it  is  promi- 
nent.    Slides  with  sharp  points  of  light  show  the  defect  more  promi- 


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Fig.   33.     Section  Through  the  Glasses  of  a 
Projecting  Lens  of  the  Petzval  Type 

nently  than  slides  having  only  lines,  while  slides  showing  scenes 
without  sharply  cut  features  near  the  edges  will  not  show  the  astig- 
matism at  ail.  In  any  picture  projected  with  the  astigmatic  lens  the 
corners  must  be  sacrificed  to  improve  the  central  portion  of  the  view, 
for  the  astigmatic  lens  usually  is  a  cheap  lens  and  lacks  in  angle  of 
view  as  well  as  in  the  correction  for  astigmatism. 

An  achromatic  lens  is  one  which  will  project  white  light  without 
making  color  fringes  along  every  sharp  edge  between  light  and 
shadow  in  the  picture.  White  light  is  composed  of  many  colored 
rays,  and  a  single  piece  of  glass,  such  as  a  glass  prism,  will  separate 
the  colors.  The  cheapest  form  of  lens  also  will  separate  the  colors, 
as  may  be  seen  with  a  cheap  reading  glass  which  colors  the  edges  of 
black  letters  upon  a  white  sheet.  The  projection  lens  must  keep 
the  lines  clear  of  colors.  Do  not  blame  the  lens  for  coloring  which 
is  due  to  the  arc  being  out  of  adjustment.  Coloring  in  the  pictures 
caused  by  lack  of  adjustment  of  the  arc  will  color  the  whites  of  the 
picture  in  blotches,  while  a  poor  lens  will  give  a  clear  white  in  the 


52 


OPTICAL  LANTERN  43 

middle  of  a  large  white  area  but  will  color  the  edge  where  black  meets 
white  in  a  sharp  Une,  particularly  toward  the  margins  of  the  picture. 

A  rectilinear  lens  is  one  which  will  project  a  straight  line  of  the 
slide  as  a  straight  line  in  the  picture  on  the  screen.  The  straight 
line  of  the  mask  or  edge  of  the  picture  of  the  slide  is  a  line  coming 
under  this  rule,  and  a  rectilinear  lens  is  required  to  give  straight 
edges  to  the  picture.  Rectilinear  lenses  have  their  glasses  separated 
into  two  groups,  as  shown  in  Fig.  33,  for  the  Petzval  form  of  lens, 
one  group  of  glasses  being  mounted  in  the  front  end  of  the  lens  tube 
and  the  other  in  the  back  end,  and  each  of  the  two  groups  having 
two  glasses  to  give  achromatic  correction. 

The  next  consideration  in  the  projection  lens  is  the  angle  of  the 
cone  of  light  which  it  will  handle.  This  requirement  rises  from 
the  fact  that  the  slide  is  not  always  placed  centrally  with  the  axis  of 
the  lens.  Its  manifestation  on  the  picture  screen  usually  takes  the 
form  of  dark  corners  at  the  two  lower  corners  of  the  picture.  Wlien 
the  axis  of  the  lens  is  shifted  to  correct  the  corners,  the  sides  of  the 
picture  become  inclined  toward  each  other,  even  with  a  rectilinear 
lens,  and  the  "keystone"  picture  results.  In  addition  to  being  achro- 
matic, rectilinear,  and  anastigmatic,  therefore,  the  projection  lens 
should  have  a  sufficiently  wide  angle  to  bring  up  the  corners  of  the 
picture  without  giving  the  picture  the  keystone  shape  to  such  an 
extent  as  to  be  objectionable.  Even  the  cheapest  lenses  for  pro- 
jection purposes  are  rectilinear  and  achromatic;  anastigmatic  and 
wide-angle  lenses  may  be  had  if  one  wishes  to  pay  for  them. 

Lenses  for  Given  Requirements.  To  select  a  lens  for  the  pro- 
jection of  lantern  slides  in  a  particular  theater  requires  that  the 
distance  from  the  picture  screen  to  the  projection  machine,  called 
the  "length  of  throw,"  be  measured,  and  that  note  be  taken  of  the 
offset  distance  of  the  projection  machine,  i.  e.,  the  distance  to  the 
side  or  toward  the  ceiling  from  the  line  of  the  center  of  the  picture 
on  the  screen. 

If  the  distance  from  a  horizontal  line  from  the  middle  of  the 
picture  on  the  screen,  measured  from  the  lens  to  the  line,  is  not 
greater  than  one  foot  for  each  ten  feet  of  throw,  it  is  likely  that  a  good 
picture  will  be  secured  with  a  narrow  angle  lens.  That  is,  for  example, 
as  follows:  Wliere  the  screen  is  vertical,  either  upon  a  wall  or  on  a 
drop  curtain  of  a  stage,  the  point  of  the  middle  of  the  picture  prob- 


53 


44  THE  :\I®TION  PICTURE 

ably  will  be  slightly  above  the  middle  of  the  screen,  because  the  top 
of  the  picture  will  be  thrown  to  the  top  of  the  screen,  the  bottom  of 
the  picture  being  above  the  bottom  of  the  screen.  With  the  projec- 
tion machine  in  the  middle  of  the  house  at  the  rear,  facing  the  screen, 
then  the  height  of  the  middle  of  the  picture  on  the  screen  may  be  com- 
pared with  the  height  of  the  lens  of  the  projection  machine.  Usually 
the  lens  of  the  projection  machine  is  above  the  height  of  the  middle 
of  the  picture  on  the  screen.  Now  with  a  sixty-foot  throw  and  the 
lens  more  than  six  feet  higher  than  the  middle  of  the  picture,  there 
will  be  a  compromise  between  a  sharp  picture  and  a  keystone  picture 
unless  a  wide  angle  lens  is  obtained.  With  a  throw  of  one  hundred 
feet,  the  lens  may  be  ten  feet  higher  than  the  middle  of  the  picture 
before  the  trouble  becomes  aggravated.  With  short  throws  from 
an  elevated  position  in  the  room  a  very  wide  angle  of  lens  shoukl  be 
obtained  if  possible.  The  feature  of  the  lens  angle  is  illustrated  in  a 
diagram  in  connection  with  the  focusing  of  the  picture  upon  the 
screen.  The  requirement  of  greatest  prominence,  and  sometimes 
the  only  requirement  considered  in  selecting  a  lens,  is  the  length  of 
the  lens  focus. 

Length  of  Lens  Focus.  For  the  purposes  of  the  projecting 
stereopticon,  the  length  of  focus  of  a  lens  may  be  defined  as  the 
distance  from  the  center  cf  the  lens  tube  to  the  lantern  slide  when  the 
slide  is  in  focus  upon  the  screen;  but  the  real  focal  length  is  just  a  little 
shorter,  and  the  focal  length  is  determined  by  the  length  of  throw 
and  the  size  of  the  picture  required  upon  the  screen,  the  lens  being 
properly  adjusted  to  the  slide  distance  afterward. 

The  focal  length  of  a  lens  may  be  measured  also  by  focusing 
the  image  of  the  sun  upon  a  card  and  measuring  from  the  middle 
of  the  lens  to  the  card,  or  by  focusing  the  light  of  a  distant  window 
upon  a  Vvhite  card  initil  the  lines  of  the  window  are  sharp  and  then 
measuring  the  distance  from  the  center  of  the  lens  tube  to  the  card. 
The  lens  length  recjuired  for  lantern  slides  for  a  given  theater  is  most 
easily  obtained  from  a  lens  table. 

Lens  Table.  Table  T  gives  the  size  of  the  picture  upon  the 
screen  for  difi'erent  lengths  of  lenses  and  different  lengths  of  throw, 
when  lantern  slides  are  projected.  At  the  left  is  given  the  lengths  of 
the  different  lenses  considered,  from  5  inches  to  24  inches.  The 
columns  at  the  right  of  the  first  column  are  arranged  each  for  a 


54 


OPTICAL  LANTERN 


45 


TABLE  I 

Size  of  Screen  Image  When  Lantern=Slides  Are  Projected 

Size  of  Mat  Opening  2|  by  3  Indies 


■< 

U   «   OD   ,* 

Length  of  Throw 

Pi<  a  (a  a 

1 

S  K  fc,  Z 

0^^  C"" 

15 

20 

25 

30 

35 

■40 

45 

50 

GO 

70 

SO 

90 

100 

3 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

5 

8.0 

8.8 

10.8 
11.8 

13.5 
14.8 

16.3 
17.8 

19.0 
20.8 

5'j 

7.3 
7.9 

9.8 
10.7 

12.3 
13.4 

14.8 
16.1 

17.3 

18.8 

19.8 
21.6 

G 

G.6 

8.9 

11.2 

13.5 

15.8 

18.1 

20.4 

7.3 

9.8 

12.3 

14.8 

17.3 

19.8 

22.3 

(5' 

G.l 

8.2 

10.4 

12.5 

14.G 

16.7 

18.8 

6.7 

9.0 

11.3 

13.6 

15.9 

18.2 

20.5 

■" 

5.7 

7.6 

9.6 

11.6 

13.5 

15.5 

17.5 

19.4 

6.2 

8.3 

10.5 

12.6 

14.8 

16.9 

19.0 

21.2 

"i 

5.3 

7.1 

8.9 

10.8 

12.6 

14.4 

1G.3 

18.1 

5.S 

7.8 

9.8 

11.8 

13.8 

15.8 

17.8 

19.8 

8 

6.6 

8.4 

19. 1 

11.8 

13.5 

15.2 

17.0 

20.4 

7.3 

9.1 

11.0 

12.9 

14.8 

16.6 

18.5 

22.3 

8h 

6.2 

7.9 

9.5 

11.1 

12.7 

14.3 

16.0 

19.2 

6.8 

8.6 

10.3 

12.1 

13.9 

15.6 

17.4 

20.9 

9 

5.9 

7.4 

8.9 

10.5 

12.0 

13.5 

15.1 

18.1 

21.1 

6.4 

8.1 

9.8 

11.4 

13.1 

14.8 

16.4 

19.8 

23.1 

'■»/ 

5.6 

7.0 

8.5 

9.9 

11.4 

12.8 

14.2 

17.1 

20.0 

6.1 

7.6 

9.2 

10.8 

12.4 

14.0 

15.5 

18.7 

21.9 

10 

5.3 

.  6.6 

8.0 

9.4 

10.8 

12.2 

13.5 

16.3 

19.0 

21.8 

5.8 

7.3 

8.8 

10.3 

11.8 

13.3 

14.8 

17.8 

20.8 

23.8 

12 

5.5 

6.6 

7.8 

8.9 

10.1 

11.2 

13.5 

15.8 

18.1 

20.4 

G.O 

7.3 

8.5 

9.8 

11.0 

12.3 

.14.8 

17.3 

19.8 

22.3 

14 

5.6 

6.6 

7.6 

8.6 

9.6 

11.6 

13.5 

15.5 

17.5 

19.4 

6.2 

7.3 

8.3 

9.4 

10.5 

12.6 

14.8 

1G.9 

19.0 

21.2 

IG 

5.8 

6.6 

7.5 

8.4 

10.1 

11.8 

13.5 

15.2 

17.0 

6.3 

7.3 

8.2 

9.1 

11.0 

12.9 

14. S 

16.6 

18.5 

18 

5.1 

».9 

G.6 

7.4 

8.9 

10.5 

12.0 

13.5 

15.1 

5.G 

G.4 

7.3 

8.1 

9.8 

11.4 

13.1 

14.8 

16.4 

20 

5.3 

6.0 

6.6 

8.0 

9.4 

10.8 

12.2 

13.5 

5.S 

6.5 

7.3 

8.8 

10.3 

11.8 

13.3 

14.8 

22 

5.4 

6.0 

7.3 

8.5 

9.8 

11.0 

12.3 

5.9 

6.6 

7.9 

9.3 

10.7 

12.0 

13.4 

24 

5.5 
6.0 

6.6 
7.3 

7.8 
8.5 

8.9 
9.8 

10.1 
11.0 

11.2 
12.3 

55 


46  THE  MOTION  PICTURE 

different  length  of  throw,  the  length  of  throw  being  mentioned  at  the 
top  of  the  column. 

With  each  length  of  lens  there  are  two  figures  for  each  length  of 
throw,  viz,  the  height  and  the  width  of  the  picture  upon  the  screen. 

This  table  works  "both  ways"  in  that  it  tells  the  size  of  picture 
when  the  lens  length  and  the  screen  distance  are  known  in  advance, 
or  it  will  tell  the  lens  length  required  to  give  a  picture  of  a  desired 
size  when  the  screen  distance  and  the  picture  size  are  known.  The 
f(jllowing  examples  show  the  use  of  the  table : 

(1)  With  a  house  in  which  the  screen  is  to  be  forty  feet  from  the  pro- 
jection machine,  it  is  desired  to  project  a  lantern-slide  picture  about  9  feet 
sq&are.  In  the  table,  the  column  is  taken  which  has  "40  ft."  at  its  top,  being 
the  sixth  of  the  narrow  columns,  counting  from  the  left,  and  in  this  column 
the  pairs  of  figures  are  examined  until  a  suitable  pair  is  found;  in  this  column 
there  is  a  pair  of  figures,  8.9  and  9.8,  and  at  the  left,  in  the  first  column  of  the 
table  is  the  figure,  12.  The  meaning  is  that  a  12-inch  lens  with  the  40-ft. 
throw  of  the  theater  will  give  a  picture  (from  a  lantern  slide  with  a2|"  X3" 
opening  in  the  mask,  the  usual  song-slide  size),  which  will  measure  upon  the 
screen  a  little  less  than  9  feet  in  height  and  very  nearly  10  feet  in  width. 

(2)  An  operator  is  obliged  to  project  lantern  slides  in  a  room  where 
for  convenience  in  placing  his  projector  it  must  be  25  feet  from  the  picture 
screen.  He  has  three  lenses  for  the  lantern,  6-inch,  8-inch,  and  10-inch. 
Which  shall  he  use  to  get  proper  results  at  first  trial,  and  not  reveal  a  lack  of 
skill  and  experience  by  making  experiments  before  an  audience?  In  the 
25-foot  column  and  opposite  the  figure  6  of  the  first  column  are  found  the 
figures,  11.2  and  12.3;  in  the  same  25-ft.  column  and  opposite  the  figure  8 
in  the  first  column  are  found  the  figures,  8.4  and  9.1;  in  the  same  25-ft.  column 
and  opposite  the  figure  10  of  the  first  column  are  found  the  figures,  6.6  and 
7.3;  the  meaning  is  that  the  6-inch  lens  will  give  a  picture  about  11  ft.  X  12  ft.; 
the  8-inch  lens  will  give  a  picture  about  8  ft.  X9  ft.;  and  the  10-inch  lens  will 
give  a  picture  about  6  ft.  X7  ft.  The  operator  then  measures  or  estimates 
the  size  of  the  screen  and  picks  the  lens  which  will  give  the  largest  picture 
that  the  screen  will  hold. 

(3)  To  change  the  size  of  the  picture,  the  table  may  be  worked  both 
ways  at  once,  as  it  were,  taking  the  results  by  an  inspection  of  the  table  by 
differences,  since  the  olsject  is  to  make  a  difference  in  the  size  of  the  picture 
now  being  projected  by  making  a  difference  in  the  length  of  the  lens  used. 
With  a  45-ft.  throw  and  a  9-inch  lens,  the  picture  is  too  large.  Going  into  the 
table  to  find  the  size  of  picture,  it  is  found  to  be  14.8  ft.  wide,  or  about  14  ft. 
9^  in.  Now  taking  the  table  to  find  the  size  of  lens  for  a  smaller  picture,  the 
9J-inch  lens  gives  a  picture  14  ft.  wide;  thus,  by  the  table,  a  difference  of  half 
an  inch  in  the  length  of  the  lens  makes  a  difference  of  dh  inches  in  the  width 
of  the  picture.  By  actual  measurement  on  the  screen,  the  projected  picture 
with  the  old  lens  may  be  several  inches  different  from  the  size  given  in  the 
table,  but  the  difference  in  the  table  for  the  difference  in  the  lenses  will  hold 
good,  and  is  the  safest  way  to  figure  for  a  new  lens. 


56 


OPTICAL  LANTERN  47 

To  obtain  the  focal  length  of  a  lens  accurately,  put  it  in  a  photo- 
graphic camera  and  focus  upon  any  object,  say  a  strip  of  paper 
three  inches  long  pasted  upon  a  window  pane,  until  the  image  on  the 
ground  glass  is  exactly  the  size  of  the  object  itself.  Then  the  focal 
length  of  the  lens  is  one-quarter  of  the  distance  from  the  ground  glass 
to  the  object  itself. 

Estimating  Lens  Length.  In  estimating  the  lens  length  to  fill 
a  given  screen  with  a  given  throw,  a  margin  should  be  left  upon  the 
screen  all  around  the  picture.  Many  lantern  slide  masks  are  not 
exactly  centered  wath  reference  to  the  position  of  the  opening  of  the 
mask  and  the  edges  of  the  glass  plates.  ]\Iany  slides,  and  particularly 
announcement  slides,  will  exceed  the  usual  standard  limit  of  2|  X  3 
inches,  running  even  to  3  inches  in  height  and  3^^  inches  in  width. 
A  single  slide  which  runs  over  the  edge  of  the  screen  in  an  evening's 
exhibition  will  discredit  the  theater.  It  does'not  create  in  the  minds 
of  the  audience  the  proper  thought  that  the  slid*  maker  has  been  in 
error,  that  the  slide  is  abnormal  and  too  large  for  the  screen,  but 
creates  instead  the  thought  that  the  screen  is  too  small  for  the  slide 
or  that  the  operator's  skill  is  too  small  for  his  job,  and  that  the  theater 
is  a  small  caliber  place  in  general. 

Calculating  Lens  Data  Without  the  Table.  The  rule  used  is  the 
"rule  of  three"  or  the  rule  of  simple  proportion  among  four  quantities; 
three  being  known,  the  fourth  always  may  be  found  by  simple  arith- 
metic. 

For  practical  purposes,  the  rule  may  be  taken,  that  the  slide  is 
to  the  'picture  as  the  focal  length  is  to  the  throw.  That  is,  the  propor- 
tion between  the  size  of  the  mask  window  in  the  slide  and  the  picture 
as  projected  upon  the  screen  is  the  same  as  the  proportion  between 
the  focal  length  of  the  projecting  lens  and  the  distance  of  throw, 
lens   to  screen. 

To  make  this  rule  available  for  arithmetic,  it  is  placed  in  the  foj-ra 

Slide   :  Picture   ::  Focal  length    :  Throw 

from  which  the  equation  is  taken 

Focal  length  X  Picture  size  =  Slide  size  X  Throw 

This  equation  works  out  for  the  height  or  width  of  the  picture, 
according  as  the  height  or  width  of  the  slitle  is  taken.     Taking  any 


57 


^8  THE  MOTION  PICTURE 

three  of  these  measurements  as  known,  the  remaining  measurement 
may  be  obtained,  as  follows: 

For  Lens  Length.  Multiply  together  the  slide  size  (say  3  inches 
wide)  and  the  length  of  throw  measured  from  the  lens  to  the  middle 
of  the  picture  screen,  taking  both  in  inches.  The  result  is  to  be 
divided  by  the  width  of  picture  which  it  is  desired  to  project  upon 
the  screen,  also  taken  in  inches,  and  the  final  answer  thus  found 
will  be  the  length  of  focus  of  the  lens,  in  inches,  which  will  be  needed. 
All  measurements  must  be  reduced  to  inches  before  multiplying  and 
dividing. 

In  calculating  for  the  projection  of  lantern  slides  upon  a  screen 
used  also  for  motion  pictures,  it  must  be  remembered  that  the  shape 
of  the  lantern-slide  picture  is  different  from  that  of  the  motion  picture; 
if  the  screen  takes  the  shape  of  the  motion  picture,  the  lantern-slide 
picture  cannot  be  made  to  fill  it,  and  should  be  calculated  for  height, 
not  for  width.  With  a  motion  picture  9  ft.  Xl2  ft.,  the  lantern-slide 
picture  will  be  9  ft.  X 10  ft.  or  10  ft.  X 1 1  ft.  to  secure  the  most  pleasing 
effect  in  changing  from  one  to  the  other  quickly. 

Example.  Calculating  lens  length.  For  a  30-ft.  throw,  it  is  desired  to 
project  a  picture  10  ft.  wide.  30  ft.  is  360  inches  and  10  ft.  is  120  inches.  The 
slide  is  3  inches  wide.  3X360  (sHde  size  multiphed  by  throw)  gives  1080; 
then  1080  ^  120  (the  first  result  divided  by  the  picture  size  desired)  gives  as 
an  answer,  9,  meaning  that  a  lens  of  9-inch  focal  length  will  give  the  desired 
size  of  picture  at  that  throw.  The  picture  will  be  slightly  smaller,  because 
the  distance  from  the  slide  to  the  lens  is  slightly  greater  always  than  the 
actual  focal  length  of  the  lens.  The  lens  table  gives  the  size  of  picture  with 
a  9-inch  lens  at  30  ft.  as  9.8  ft.,  or  9  ft.  95  in.,  or  about  2k  in.  smaller  than  the 
simple  arithmetical  calculation. 

For  Picture  Size.  INIultiply  together  the  slide  size  in  inches 
and  the  length  of  throw  in  inches,  then  divide  by  the  focal  length  of 
the  Ions  in  inches.  The  picture  projected  will  be  only  a  trifle  smaller 
than  the  answer  obtained. 

Ex.\Mi'LE.  Calculating  size  of  picture  with  any  lens.  With  a  throw  of 
35  ft.  and  a  10-in.  lens,  reduce  the  throw  to  inches,  420  inches,  multiply  by 
the  width  of  the  slide.  3  X  420  (slide  size  multiplied  by  throw  in  inches) 
gives  1260;  then  1260  -^  10  (the  first  result  divided  by  the  length  of  the  lens 
in  inches)  gives  12  ft.  0  in.     Here  the  table  gives  12.3  ft.,  or  12  ft.  3^  in. 

For  Slide  Size.  It  might  seem  that  the  operator  would  not 
have  this  calculation  to  make,  since  as  an  operator  he  would  not 


68 


a  -g 


OPTICAL  LANTERN  49 

have  to  make  slides.  It  is  involved  in  the  making  of  emergency 
slides  where  the  operator  wishes  to  cut  the  mask  with  the  largest 
opening  which  can  be  projected  upon  his  screen.  It  is  involved  in 
the  selection  of  announcement  slides,  which  have  mask  windows 
of  different  sizes,  many  of  them  too  large  for  the  operator's  picture 
screen.  By  this  calculation,  the  operator  may  determine  the  largest 
slide-mask  window  which  his  screen  will  take  with  the  lens  he  is 
using,  aaid  can  select  announcement  slides  which  fall  within  the 
limiting  dimensions. 

Multiply  together  the  focal  length  of  the  lens  and  the  size 
of  the  picture  projected  or  which  it  is  desired  to  project,  in  inches. 
Divide  the  result  by  the  throw  in  inches.  The  final  answer  will  be 
the  dimension  which  in  the  slide  window  will  fill  the  screen  as  de- 
sired when  projected.  If  the  width  of  picture  has  been  taken  in 
the  calculation,  the  result  will  give  the  width  of  the  slide-mask  window. 
If  height  of  the  picture  has  been  taken  in  the  calculation,  the  result 
will  give  the  height  of  the  slide  mask  window. 

Example.  Calculating  slide-mask  window.  With  a  throw  of  30  ft. 
and  with  a  10-in.  lens,  the  screen  is  8  ft.  9  in.  by  10  ft.  G  in.  By  the  table 
the  10-inch  lens  gives  a  picture  8  ft.  by  8.8  ft.,  or  8  ft.  by  8.  ft.  9^  in.  It  is 
desired  to  fill  the  screen  within  a  few  inches,  to  project  a  picture,  say,  8  ft.  G  in. 
by  10  ft.  3  in. 

For  the  width,  10X123  (the  focal  length  of  the  lens  in  inches  multiplied 
by  the  desired  width  of  the  picture  in  inches)  gives  1230;  1230  -^  360  (the 
first  result  divided  by  the  throw  in  inches)  gives  3i^3  as  the  final  answer.  The 
sliJe-mask  window  may  be  about  3J  inches  wide. 

For  the  height,  10  X  102  (the  focal  length  of  the  lens  in  inches  multiplied 
by  the  desired  height  of  the  picture  in  inches)  gives  1020;  1020  -^  3G0  (the 
first  result  divided  by  the  throw  in  inches)  gives  2'  as  the  final  answer.  The 
slide  mask  may  be  about  2|  by  3  J  inches  to  fill  the  screen. 

For  Length  cf  Throw.  This  calculation  is  required  when  the 
operator,  having  but  one  lens  availalile,  must  determine  how  far 
from  the  screen  to  place  his  projection  machine  to  secure  a  picture 
of  the  desired  size.  Aside  from  private  exhibitions,  in  parlors  or 
improvised  halls,  it  has  little  value. 

Midtiphj  the  focal  length  of  the  lois  by  the  desired  picture  size 
and  divide  by  the  slide  size,  talcing  all  dimensions  in  inches.  The 
answer  will  be  the  distance  in  inches  from  projection  machine  to 
screen,  or  length  of  throw. 


59 


50  THE  MOTION  PICTURE 

Example.  Calculation  of  length  of  throw.  The  operator  has  but  a  6- 
inch  lens,  and  the  screen  provided  is  5  X  6  ft.  Taking  5  ft.  6  in.  as  the  widest 
picture  safe  for  the  size  of  screen,  6  X  66  (focal  length  in  inches  multiplied 
by  picture  wndth  in  inches)  gives  396;  396  -^  3  (first  result  divided  by  width 
of  slide  mask  window  in  inches)  gives  132  inches,  or  11  feet  as  the  length  of 
throw. 

If  an  8-inch  lens  were  available,  the  calculation  would  give  8  X  66  ^  3, 
equal  to  14  ft.  8  in.  as  the  length  of  throw.  Such  small  dimensions  as  these, 
met  only  in  private  exhibitions,  will  not  be  found  in  any  table,  and  when 
such  dimensions  are  encountered  the  rule  for  calculation  without  the  table 
becomes  of  use. 

Accurate  Calculations.  The  distance  from  the  lens  to  the 
lantern  slide  always  is  a  little  greater  than  the  focal  length  of  the 
lens.  This  difference  has  been  omitted  from  the  foregoing  rules 
because  the  variation  is  small  in  the  final  results  and  within  the 
variations  of  probable  error  in  taking  the  measurements  in  the  first 
place. 

For  greater  accuracy,  the  length  of  throw  should  be  taken  along 
the  axis  of  the  projection  lens  or  of  the  optical  .system.  Let  T  equal 
this  length  of  throw,  lens  to  screen,  F  equal  equivalent  focal  length 
of  the  lens,  *S  the  slide-mask  window  dimension,  and  P  the  corre- 
sponding picture  dimension,  all  dimensions  being  taken  in  inches 
or  in  the  same  unit. 

By  the  law  of  optics  which  may  be  called  the  "LaAV  of  the  Rela- 
tion of  Image  Sizes," 

S   :  P  ::  D   :  T 

ST  =  PD  (1) 

By  the  law  of  optics  known  as  the  "Law  of  Conjugate  Foci," 

D-F  :  F  :  :  F  :  T-F 

F-  =  {D-F){T-F)  (2) 

These  two  equations  include  five  variables,  *S,  P,  D,  T,  and  F, 
of  which  the  value  of  the  variable  D  never  is  recjuired  in  practice. 
Of  the  remaining  four  variables,  S,  P,  T,  and  F,  when  any  three 
of  the  four  are  taken  as  known  or  assumed  or  desired,  the  remain- 
ing one  may  be  determined  accurat-ely  by  the  operations  of  simple 
algebra. 

As  the  final  focus  is  obtained  by  shifting  tJie  position  of  the  lens, 
and  as  the  position  of  the  lens  depends  upon  its  focal  length,  which 


60 


(I 


OPTICAL  LANTERN  51 

focal  length  has  not  been  determined  as  yet  at  the  time  of  measuring 
for  the  dimensions  for  the  calculation,  the  only  distance  which  can 
be  measured  along  the  axis  of  the  optical  system  is  the  distance  from 
the  slide  to  the  screen.  Let  H  equal  the  distance  from  the  slide  to 
the  screen,  then,  by  the  premises  of  the  problem, 

D+T-==H  (3) 

From  the  three  equations  (1),  (2),  and  (3),  any  one  of  the  four 
dimensions,  S,  P,  II,  and  F,  may  be  determined  accurately,  when 
the  remaining  three  are  known  or  assumed  or  desired. 

Lens  Construction  and  Adjustments.  Projection  lenses  are  made 
up  of  a  number  of  glasses,  at  least  two,  front  and  back,  the  focal 
length  of  each  glass  being  greater  than  the  resulting  focal  length  of  the 
combination.  If  still  another  glass  were  added  to  the  combination, 
the  focal  length  would  be  reduced  as  a  result  of  the  addition.  Lenses 
of  small  curvature  in  clip-cap  holders,  similar  to  that  shown  in  Fig. 
34,  may  be  used  to  change  the  size  of  pictures  slightly  and  at  a  very 
small  cost.  The  size  of  a  picture  may  be  decreased  by  ten  per  cent 
in  this  way,  and  by  the  use  of  a  "negative  lens"  similarly  mounted 
in  a  cap,  the  size  of  the  picture  may  be  increased  slightly. 

Care  of  Lenses.  Every  day,  wipe  the  out- 
side surface  of  the  lenses  with  a  soft  camel's  hair 
brush,  without  taking  the  lenses  from  the  tube 
or  the  tube  from  the  holder.  The  hair  of  the 
brush  should  be  an  inch  long,  without  any  stiff- 
ness whatever.  The  type  of  brush  known  as 
"camel's  hair  pencil,"  consisting  of  a  bunch  of 
camel's  hair  drawn  into  a  quill,  is  suitable,  a 
large  size  of  pencil  (yet  smaller  than  a  lead 
pencil)  being  chosen.  In  wiping  the  surface  of  ^^"-  ^^  .^iHar^^f  ^^°^' 
the   lens,  the  brush  should  not  be  bent  to  rub 

the  lens  with  the  quill  or  handle,  but  to  stroke  the  glass  with  the 
hair  of  the  brush  to  sweep  away  dust  grains  or  fine  particles  of 
lint  which  may  have  floated  to  the  surface  of  the  lens.  Keep  the 
brush  in  an  envelope,  such  as  is  used  for  mailing  letters,  when  not 
in  use  that  it  may  not  collect  dust.  The  movement  of  the  brush 
is  to  sweep  away  dust  grains,  not  to  polish  the  glass  or  clean  it  of 
finger  marks.     If   the  glass  gets   finger   marks,  more  violent  treat- 


61 


52 


THE  MOTION  PICTURE 


ment,   say  with  an   extra  soft  chamois,  is  necessary  to  wipe  them 
away;  keep  the  chamois  also  in  an  envelope  away  from  dust. 

"With  time — and  it  is  a  matter  of  months-  rather  than  of  days — 
lenses  will  acquire  a  gray  film  upon  their  inside  surfaces.  This  may 
be  removed  by  washing  with  alcohol  and  Aviping  with  a  dry,  soft 
cotton  rag,  then  polishing  with  soft  chamois.  The  alcohol  should 
be  J  alcohol  and  f  water,  as  the  pure  alcohol  will  dry  upon  the  sur- 
face of  the  lens  so  cjuickly  that  it  will  leave  the  surface  as  bad  as  be- 
fore. In  taking  out  the  lenses,  lay  them  carefully  and  in  order  upon 
the  table  where  you  are  worlcing,  then  take  them  up  one  only  at  a 
time,  cleaning  it  carefully  and  putting  it  back  in  its  proper  position, 
so  that  there  will  be  no  possibility  of  a  mix-up  when  they  are  put  back 
in  the  tube.     Once  a  year  is  often  enough. 

FOCUSING 

The  general  subject  of  focusing  is  involved  throughout  the  ad- 
justment of  the  Optical  system  of  the  lantern,  and  focusing  the  light 
has  particularly  to  do  with  the  adjustment  of  the  lamp  with  reference 


Fig.  35.     Diatrram  of  a  Slide  in  Focus  upon  (he  Picture  Screen 

to  the  position  of  the  arc  relative  to  the  condensers.  The  relation  of 
the  projected  image  to  the  screen  upon  which  it  is  to  be  viewed  now 
will  be  considered. 

The  final  focus  is  attained  by  moving  the  stereo  lens  slightly 
forward  or  backward  in  its  holder  to  bring  the  converging  rays  of 
light  into  focus  upon  the  picture  screen.  From  each  point  of  the 
lantern  slide  a  bundle  of  rays  passes  to  the  lens,  striking  all  over  the 
back  surface  of  the  lens,  being  bent  within  the  lens  and  passing  out 
of  it  practically  from  all  over  the  surface  of  the  front  glass;  then  the 
bundle  begins  to  draw  together  and  finally  converges  into  practically 


62 


OPTICAL  LANTERN 


53 


a  single  point,  or  very  small  spot  of  light.  The  distance  of  this  spot 
from  the  lens  is  dependent  upon  the  distance  of  the  lens  from  the  slide, 
and  by  proper  adjustment  of  the  position  of  the  lens,  the  sharp  focus 
of  the  bundle  of  rays  may  be  made  to  occur  upon  the  surface  of  the 
picture  screen.     This  gives  the  condition  illustrated  in  Fig.  35.     The 


Fig.  3G. 


Diagram  of  a  Slide  Out  of  Focus  Upon  the  Picture  Screen. 
Lens  too  far  from  Slide 


lantern  slide  is  at  the  left,  the  lens  near  it,  and  the  picture  screen  is 
at  the  extreme  right.  The  bundles  of  rays  from  the  lens  meet  upon 
the  screen  surface. 

For  illustration  of  the  out-of-focus  conditions,  Fig,  36  is  given, 
illustrating  the  condition  when  the  lens  is  too  far  from  the  lantern 
slide,  and  Fig.  37  is  given,  illustrating  the  condition  when  the  lens 
is  too  close  to  the  slide. 

In  Fig.  36,  the  converging  bundles  of  rays  leaving  the  lens 
cross  before  they  get  to  the  picture  screen  and  spread  again,  reaching 


Fig.  37. 


Diagram  of  a  Slide  Out  of  Focus  Upon  the  Picture  Screen. 
Lens  too  close  to  Slide 


the  screen  slightly  spread  out,  the  different  adjacent  bundles  blend- 
ing into  each  other  and  producing  the  blurred  effect  upon  the  screen 
well  knowTi  as  a  slide  out  of  focus.  The  true  focus  of  the  image 
is  at  the  dotted  line  drawn  across  the  rays  at  the  point  of  crossing  of 


63 


54  THE  MOTION  PICTURE 

each  of  the  bundles  of  light.  This  would  be  the  proper  position  of 
focus  for  the  lens  if  the  screen  were  nearer,  and  the  image  is  corre- 
spondingly smaller,  in  proportion  to  the  lesser  distance  of  the  screen 
from  the  lens.  This  diagram  shows  clearly  how  the  nearer  screen 
or  shorter  "length  of  throw"  gives  a  smaller  picture  upon  the  screen 
for  the  same  lens,  or  same  focal  length  of  lens,  as  shown  by  the  lens 
table.  The  "focal  plane"  or  "image  plane"  represented  at  the  dotted 
line  of  Fig.  36  may  be  moved  forward  toward  the  picture  screen  at  the 
right  of  the  figure  by  mo\'ing  the  lens  back  toward  the  lantern  slide. 

In  Fig.  37,  the  lens  is  shown  moved  too  far  toward  the  slide. 
The  converging  bundles  of  rays  now  do  not  meet  before  they  reach 
the  screen,  nor  even  at  the  screen,  so  that  the  result  is  a  blur  in  the 
projected  image,  as  before;  as  a  matter  of  fact  the  rays  would  meet 
far  to  the  right  of  the  diagram,  producing  a  xery  large  picture  upon 
a  more  distant  screen. 

The  best  adjustment  for  focus  is  attained  only  by  experimental 
adjustment,  moving  the  lens  forward  until  it  is  just  a  little  too  far, 
then  moving  it  backward  until  it  is  just  a  little  too  near,  then  taking 
a  position  between.  With  a  cheap  lens,  sharp  focus  may  not  be 
obtained  all  over  the  field  of  the  picture  screen  at  once,  because  of 
the  feature  of  curvature  of  field,  or  cun^ature  of  the  image  surface. 

Curvature  of  Image.  The  surface,  or  the  imaginary  surface, 
upon  which  the  image  is  brought  into  focus  has  been  called,  as  quoted, 
the  "focal  plane"  or  "image  plane"  because  it  ought  to  be  a  plane 
or  flat  surface.  To  make  it  so,  or  even  approximately  so,  requires 
specially  constructed  lenses  for  projection,  involving  usually  a  greater 
number  of  glasses  in  the  lens  tube  and  a  correspondingly  greater 
amount  of  labor  and  skill  in  manufacture  and  correspondingly  higher 
prices  to  the  purchaser  of  the  lens. 

Curvature  of  the  image  is  illustrated  in  diagram  in  Fig.  38; 
the  slide  is  represented  at  SL  with  its  surface  flat,  as  it  always  is; 
the  lens  is  sho^v^l  at  0,  and  the  image  is  shown  at  7  in  a  curved  line. 
This  diagram  represents  a  sectional  view  through  the  center  of  the 
slide,  lens,  and  image,  taking  a  vertical  section  by  cutting  the  whole 
theater,  as  it  were,  into  halves.  The  shape  of  the  image  at  /  is  spher'crJ, 
or  saucer-shaped,  with  the  edges  jf  the  saucer  bending  toward  the 
projecting  operator  and  the  center  of  the  saucer  bent  back  toward 
the  iniddk'  (jf  the  picture  screen. 


r 


64 


OPTICAL  LANTERN 


55 


If  the  lens  be  adjusted  to  bring  the  bottom  of  the  saucer-shaped 
image  to  the  surface  of  the  screen,  there  will  be  had  a  very  sharp 
focus  in  the  middle  of  the  screen,  with  gradual  fading  away  of  detail 
toward  the  edges  of  the  screen,  the  corners  being  worst  of  all.  By 
bringing  the  lens  slightly  nearer  the  slide,  the  middle  of  the  image 
or  bottom  of  the  saucer  of  the  image  is,  theoretically,  pushed  back 
through  the  screen,  giving  a  slight  blur  in  the  exact  middle  of  the 
picture,  surrounded  by  a  broad  band  or  ring  of  sharply  focused 
image,  then  fading  slightly  again  toward  the  corners.  This  is  the 
best  condition  of  focus  where  the  effect  of  curvature  is  manifested  in 
the  lens.     The  condition  of  adjustment  with  the  center  of  the  picture 


Fig.  38.     Diagram  Showin<?  the  Curved  Ima^re  Surface  of  a  Picture 
Projected  by  au  Uncorrected  Lens 

slightly  beyond  the  picture  screen  is  illustrated  also  in  Fig.  38,  where 
the  straight  line  PS  represents  the  surface  of  the  picture  screen  and 
the  curved  line  I  represents  the  curved  line  of  the  cut  through  the 
saucer-like  image  from  the  uncorrected  lens  O. 

Remedy  for  Curvature.  The  only  remedy  for  curvature  of 
image  is  the  purchase  of  a  new  and  a  better,  more  expensive  lens. 
Such  lenses  are  advertised  as  having  a  "flat  field."  The  image  sur- 
face of  such  a  lens  will  be  sufficiently  nearly  flat  to  improve  the  picture 
beyond  the  condition  shown  in  Fig.  36,  bringing  both  center  and 
corners  into  focus  at  the  same  time  when  the  picture  screen  PS  is 
parallel  to  the  slide  SL. 

Inclined  Optical  Axis.  Very  few  theaters  offer  the  advantage 
assumed  in  Fig.  38,  that  the  center  of  the  lens  is  opposite  the 
center  of  the  picture  screen.  Sometimes  it  is  at  the  side  of  the  center, 
sometimes  it  is  far  above  the  center,  sometimes  both. 


65 


56 


THE  MOTION  PICTURE 


In  Fig.  39,  the  projection  lens  is  illustrated  as  being  placed  at 
about  the  level  of  the  top  of  the  picture  screen,  a  condition  met  in 
large  theaters  where  the  pictures  are  projected  from  the  upper  bal- 
cony,  but  not  usual  in  small   motion-picture   theaters.     The  first 


c/\  /■/ 


Fig.  39.     Diagram  of  the  Inclined  Optical  Axis 


thought,  when  the  ray  of  light  from  the  lantern  is  thrown  toward  the 
screen  and  found  to  strike  it  near  the  ceiling,  is  to  tip  the  whole  pro- 
jecting machine,  table  and  lantern  together,  to  make  the  center  of 
the  beam  of  light  strike  centrally  on  the  screen.  This  is  the  con- 
dition taken  in  Fig.  39  for  illustration  of  the  inclined  optical  axis. 
Its  results  are  shown  in  Figs.  39,  40,  and  41. 

At  the  extreme  right  of  Fig.  39  is  shown  the  vertical  picture 

screen,  and  at  the  extreme  left 

is  shown  the  projection  table 
top,  slide,  and  lens.  The  table 
top  is  represented  by  the  dotted 
parallel  lines  at  T,  showing  its 
inclination.  A  little  tilt  can  be 
endured,  but  the  degree  shown 
in  the  diagram  would  be  fatal 
to  good  pictures. 

The  slide  6'L  in  the  slide  car- 
rier remains  perpendicular  to 
the  table  top  T"  and,  therefore,  is 


Fifl 


40.    Keystone  Picture  with  Vertical 
Inclination 


tilted  with  reference  to  the  picture  screen  PS.  The  lens  O  is  parallel 
to  the  table  top  T  and  perpendicular  to  the  surface  of  the  slide  SL; 
no  advantage  would  be  gained  by  having  it  otherwise. 

The  curved  image  surface  is  represented  by  the  curved  line 


66 


OPTICAL  LANTERN 


57 


Fig.  41. 


Keystone  Picture  with  Hori- 
zontal Inclination 


CI-CI  extending  in  a  curved  line  with  its  center  opposite  the  lens  0, 
but  because  of  the  inclination  of  the  projection  machine  the  curved 
image  surface  cuts  the  picture  screen  in  but  one  place,  instead  of 
cutting  it  in  two  places  as  it  did  in  Fig.  36.  The  defect  of  curvature 
of  image  surface,  therefore,  will  be  found  to  be  made  more  objection- 
able when  the  operator  is  obliged  to  tilt  his  projecting  table  top. 
Nor  will  the  substitution  of  a 
"flat-field"  lens  correct  the  trou- 
ble altogether.  The  image  plane 
of  a  flat-field  lens  is  approxi- 
mately a  flat  surface  at  right 
angles  to  the  axis  of  the  lens. 
Such  a  surface  is  represented  by 
the  straight  line  FI-FI  for  the 
flat  image  in  Fig.  39,  but  this 
flat  image  also  cuts  the  surface 
of  the  picture  screen  PS  in  but 
one  place  and,  therefore,  will 
give  but  a  band  of  sharp  focus  across  the  picture,  the  focus  fading 
into  blur  slowly  in  either  direction,  upward  or  downward  in  the 
picture. 

The  Keystone  Picture.  Further  difficulties  are  found  in  the  shape 
of  the  projected  picture  upon  the  screen.  If  the  projection  station 
is  above  the  center  of  the  screen,  and  the  table  top  and  the  lantern 
are  tilted  downwardly,  as  shown  in  Fig.  39,  the  bottom  of  the  picture 
screen  will  be  farther  from  the  lens  than  the  top  of  the  screen.  As 
will  be  noted  from  Figs.  35,  36,  and  37,  the  farther  the  distance  from 
the  lens  to  the  screen,  the  larger  will  be  the  picture  upon  the  screen; 
hence,  as  the  bottom  of  the  screen  in  Fig.  39  is  farther  from  the 
lens  than  the  top  of  the  screen,  the  picture  thrown  upon  the  screen 
will  be  larger  at  the  bottom  than  at  the  t  /p.  This  effect  is  shown  in 
Fig.  40.  The  top  and  bottom  edges  of  this  figure  are  parallel  but 
the  sides  are  not.  It  is  the  shape  of  the  "keystone"  picture,  the 
picture  which  results  when  the  optical  axis  of  the  projecting  machine 
is  inclined,  being  tipped  downward, 

\Mien  the  projection  machine  is  placed  at  the  side  of  the  room, 
thereby  bringing  it  down  sometimes  to  the  level  of  the  middle  of 
the  screen,  the  picture  becomes  distorted  in  its  top  and  bottom  lines, 


67 


58 


THE  MOTION  PICTURE 


appearing  as  shown  in  Fig.  41,  a  shape  more  objectionable  than  that 
of  Fig.  40. 

Remedy  for  the  Keystone  Picture.  In  the  correction  of  fauhs 
such  as  this,  the  good  operator  proves  his  superiority  over  the  poorer 
one.  The  keystone  effect  may  be  entirely  corrected  for  small  angles 
by  setting  the  lantern  slide  eccentric  to  the  lens  (it  is  more  accurate 
to  state  that  the  lens  is  set  eccentrically  to  the  lantern  slide)  and 
may  be  corrected  for  still  greater  angles  by  the  eccentric  slide  in  con- 
junction with  a  good  flat-field  lens. 

The  setting  of  the  eccentric  slide  is  showni  in  diagram  in  Fig.  42. 
In  this  figure,  the  lens  O  is  above  the  level  of  the  center  of  the  picture 
screen  PS,  about  half-way  between  the  middle  line  and  the  top  line. 
The  table  top  T  is  brought  back  to  the  horizontal  position,  the  slide 


Fig.  42.     Diasram  of  tlie  Eccentric  Slide 

SL  is  vertical  to  the  table  top  and  is  parallel  to  the  picture  screen, 
both  the  picture  screen  and  the  slide  being  vertical.  The  lens  O  is 
horizontal,  parallel  to  the  table  top  and  at  right  angles  to  the  slide 
and  the  screen,  but  it  is  dropped  below  the  level  of  the  center  of  the 
slide  SL,  so  that  a  straight  line  from  the  upper  edge  of  the  mask 
window  in  the  slide  will  pass  through  the  center  of  the  lens  to  the 
bottom  of  the  picture  in  its  desired  position  on  the  screen.  The 
slide  SL  thus  is  not  in  the  center  of  the  lens  (is  "eccentric"  to  the 
lens)  and  the  projected  image  is  accordingly  displaced,  the  slide 
being  slightly  above  the  lens  in  the  lantern  and  the  image  being  much 
below  the  lens  on  the  screen. 

With  reference  to  keystone  distortion :  The  bottom  of  the  picture 
is  farther  from  the  lens,  as  it  was  in  Fig.  39,  but  the  top  of  the  lantern 
slide  also  is  farther  from  the  lens  than  the  bottom  of  the  .slide.     The 


68 


^1 


OPTICAL  LANTERN  59 

foot  of  the  slide  is  farther  from  the  lens  center  compared  with  the 
head  of  the  slide  in  just  the  same  proportion  that  the  foot  of  the 
picture  screen  is  farther  from  the  lens  center  compared  with  the  head 
of  the  picture  screen.  As  the  size  of  the  pro'jected  picture  is  wholly 
a  matter  of  proportional  distances,  the  size  of  the  picture  may  be 
worked  out  by  arithmetic  to  prove  that  the  shape  of  the  picture  is 
correct,  or  more  simply  it  may  be  tried  on  the  picture  screen  with  the 
lantern.  With  reference  to  focus:  The  curved  image  of  the  lens 
is  represented  in  Fig.  42  by  the  curved  line  CI,  and  it  crosses  the 
picture  screen  PS  in  only  one  place,  just  as  it  did  in  Fig.  39. 
While  the  focus  of  the  cheap  lens  with  the  curved  image  has 
not  been  improved,  neither  has  it  been  made  worse.  With  the  flat- 
field  lens,  however,  the  flat-image  surface  will,  be  straightened  up 
when  the  projection  table  and  slide  and  lens  are  made  level,  so 
that  the  flat  image  now  will  be  parallel  to  the  picture  screen, 
and  the  entire  picture  will  be  in  focus,  top  and  bottom,  center  and 
corners. 

Lens  Angle.  With  reference  to  the  direction  of  the  rays  of  light 
passing  through  the  lens  in  Fig.  42,  it  may  be  noticed  that  from  the 
foot  of  the  inverted  slide,  the  upper  edge  of  the  slide  in  the  diagram, 
the  rays  of  light  enter  the  lens  0  at  a  greater  angle  than  they 
enter  the  lens  of  Fig.  39.  Some  lenses  will  accommodate  a  wider 
angle  of  light  rays  than  others.  The  "wide-angle"  lenses  are  either 
larger  in  the  barrel  diameter  or  shorter  in  barrel  length,  as  com- 
pared with  a  cheaper  lens  of  the  same  focal  length  which  is  able  to 
care  for  only  the  narrower  angles  of  light.  The  length  of  focus 
can  not  be  determined  by  looking  at  a  lens  other  than  by  testing  its 
ability  to  bring  light  rays  to  a  focus,  but,  knowing  its  length  of  focus, 
the  angle  which  it  will  cover  may  be  judged  by  its  shape,  the  shorter 
length  of  barrel  almost  invariably  giving  the  wider  angle  and  giving 
greater  power  to  cover  the  lower  corners  of  the  picture  on  the  screen 
when  the  slide  is  set  off  the  center  of  the  lens.  In  photographic  lenses, 
a  lens  of  6-inch  focal  length  usually  is  used  to  cover  a  4  X  5-inch  plate, 
but  a  6-inch  lens  may  be  made  which  will  give  an  image  all  over  an 
8  X  10-inch  plate,  four  times  the  area.  The  same  difference  can  be 
found  in  projection  lenses.  If  the  lower  corners  of  the  picture  on  the 
screen  show  dark,  you  require  a  new  lens  of  shorter  barrel  and  of 
the  same  focal  length,  or  you  will  have  to  tip  the  table  a  litde  and 


69 


GO 


THE  MOTION  PICTURE 


43.     Diagram  of  the  Eccentric  Slide 
with  a  Narrow-Angle  Lens 


endure  the  keystone  effect  or  correct  it  by  a  slide-holder  keystone 
mask. 

Two  diagrams  comparing  the  work  cf  a  narrow-angle  lens  and 
a  wide-angle  lens  are  shown  in  Figs.  43  and  44.  At  the  left  of  each 
diagram  is  showm  the  lantern  slide  to  be  projected.  It  is  seen  that 
the  lens  of  Fig.  43  has  sufficient  angle  to  project  the  slide  if  the  slide 

is  placed  centrally  within  the 
solid  lines  representing  the  limits 
of  the  rays  of  light,  but  that  if 
the  slide  is  placed  eccentrically 
above  the  center  of  the  lens,  as 
shown,  the  rays  of  light  must 
pass  as  indicated  in  dotted  lines, 
and  the  lens  Avill  be  unable  to 
do  the  work.  In  Fig,  44,  how- 
ever, the  slide  as  placed  eccentrically  still  falls  within  the  work- 
inn;  angle  of  the  lens  and  the  wide-angle  feature  of  the  lens  thus 
permits  that  placing  of  the  slide  with  satisfactory  projection. 

Do  not  believe  a  salesman  who  tells  you  that  "a  lens  is  a  lens 
and  that  is  all  there  is  to  it."  Get  another  salesman.  There  are 
differences  in  lenses.  The  working  angle  of  the  lens  and  the  flatness 
of  field  or  image  are  the  two  points  in 
which  all  the  cheaper  lenses  and  some 
of  the  higher  priced  lenses  will  be  found 
lacking.  When  the  conditions  of  the 
theater  force  you  to  set  the  lens  off  the 
center  of  the  slide,  both  flatness  and 
wider  angle  will  be  needed  for  a  good 
]>rojection.  Otiierwise,  the  wider  angle 
is  a  needless  expense. 

Inclined  Screen.  To  reduce  distortion  in  the,  picture  with  a 
lens  of  narrow  angle,  the  screen  may  be  inclined  slightly,  as  shown 
in  Fig.  45.  This  brings  the  optical  system  back  to  the  fundamental 
condition  of  Fig.  1  and  of  Fig.  35.  The  inclined  screen  is  objection- 
able to  the  spectator  because  of  the  difference  in  distance  from  the  eye 
to  the  top  and  to  the  bottom  of  the  screen,  and  this  difference  will  itself 
bring  in  the  keystone  effect  to  the  spectator's  vision,  even  though 
the  picture  upon  the  screen  be  perfectly  rectilinear. 


Fia;.  44.     Diagram  of  the  Ec- 
centric Slide  with  a  Wide- 
Angle  Lens 


70 


OPTICAL  LANTERN  61 

All  of  the  remedies  for  distortion  may  be  used  at  once,  inclining 
the  screen  a  little,  tipping  the  table  a  little,  and  setting  the  lens  off 
center  a  little,  including  also  the  keystone  mask. 

The  Keystone  Mask.  The  keystone  effect  of  Fig.  40  may  be 
compensated  for,  so  far  as  the  edges  of  the  picture  are  concerned,  by 
providing  the  slide  holder  with  a  keystone  mask  for  the  window 
through  which  the  slide  is  projected,  the  edges  of  the  mask  being 
a  little  smaller  than  the  mask  of  the  slide.  Measure  the  angle  of 
inclination  of  the  sides  of  the  picture  on  the  screen  and  make  the 
sides  of  the  mask  have  the  same  angle  of  inclination.  The  top  and 
the  bottom  lines  of  the  mask  are  parallel  if  the  picture  on  the  screen 
is  true  in  that  detail.  The  mask  now  is  placed  in  the  slide-carrier 
window  with  the  narrow  edge  up;  the  lens  magnifies  the  upper  edge 
of  the  mask  because  of  the  greater  distance  to  the  picture  screen, 


Fig.  45.     Diagram  Shov.ing  the  Inclined  Picture  Screen 


and  the  keystone  mask  throws  a  rectilinear  field  of  light  upon  the 
screen.  Two  masks  will  be  needed,  one  for  each  end  of  the  slide 
carrier,  or  one  for  each  lantern  of  a  dissolver.  A  single  mask  for 
the  fixed  window  of  the  slide  holder  would  be  too  far  out  of  focus  to 
give  good  service.  The  keystone  mask  will  not  correct  the  distortion 
of  the  image  itself,  but  only  correct  the  margins  of  the  projected 
picture.  With  lantern  slides  of  varying  sizes,  only  those  larger  than 
the  keystone  mask  will  be  corrected,  and  those  of  course  are  corrected 
by  the  cutting  off  of  a  portion  of  the  edge  of  the  picture  as  seen  in  the 
mask  window  of  the  slide  itself.  With  the  motion  head,  where  all 
images  for  projection  are  of  uniform  size,  the  keystone  mask  becomes 
more  practical.  Greater  skill  is  required  in  fitting  it,  because  of  its 
smaller  size. 


71 


62  THE  MOTION  PICTURE 

LANTERN  SLIDES 

Announcement  Slides.  Commercial  announcement  slides  very 
frequently  are  over-sized.  In  selecting  them,  care  should  be  taken 
to  avoid  getting  a  slide  which  will  project  a  picture  or  field  larger  than 
the  screen. 

Emergency  Slides.  The  quickest  emergency  slide  is  made  of 
two  cover  glasses,  a  slip  of  draftsman's  tracing  paper  or  tracing  linen, 
India  ink,  and  a  binding  strip  or  piece  of  gummed  paper.  The 
mucilage  edge  of  an  envelope  flap  is  always  available  for  gummed 
paper  when  nothing  else  can  be  had.  A  lantern-slide  mask  or  win- 
dow is  desirable,  but  not  necessary.  Write  with  a  fine  pen  upon  the 
tracing  paper  or  linen,  place  between  the  glasses,  stick  together  with 
the  gummed  paper  and  put  it  into  the  lantern.  If  cover  glasses  are 
not  at  hand,  the  binding  strip  may  be  slit  on  a  couple  of  song  or 
announcement  slides  and  the  cover  glasses  thus  obtained.  This 
slide  is  improved  by  turning  the  tracing  paper  over  and  tracing 
the  writing  on  both  sides  of  the  sheet  before  putting  it  into  the  cover 
glasses. 

Cover  glasses,  masks,  and  binding  strips  should  be  at  hand  at 
all  times  for  the  repair  of  slides.  Add  to  this  equipment  a  bottle 
of  Higgins  Waterproof  Ink  and  a  supply  of  crowquill  pens  and 
tracing  paper  and  the  emergency  slide-making  set  is  complete.  Cut 
the  tracing  paper  to  lantern-slide  size,  place  a  mask  upon  each  small 
sheet,  and  run  a  sharp  pencil  around  the  window  of  the  mask,  ^^^len 
writing,  keep  the  words  inside  the  pencil  line  and  parallel  to  the  edge 
of  the  sheet. 

For  a  typewritten  slide  with  this  outfit,  cut  a  larger  sheet  of 
tracing  paper,  place  a  mask  upon  it,  and  nm  a  sharp  pencil  around 
inside  and  outside  of  the  mask.  Place  this  sheet  in  the  typewriter 
with  a  carbon  sheet  back  of  it,  the  carbon  surface  against  the  back  of 
the  tracing  paper.  Write  within  the  inner  window  line.  When 
taken  from  the  machine,  the  sheet  will  have  the  ink  of  the  ribbon 
on  one  side  and  the  carbon  of  the  transfer  paper  on  the  back,  giving 
a  double  density  for  projection.  If  the  written  matter  is  not  cen- 
tered in  the  window,  the  mask  may  be  adjusted  over  it,  the  pencil 
run  around  the  outside  of  the  mask,  and  the  sheet  trimmed  to  the 
new  margin;  then  bind  between  cover  glasses  with  gummed  paper. 


72 


OPTICAL  LANTERN  63 

Unless  skillful  in  making  the  Roman  letters,  the  script  form  of 
writing  will  produce  the  more  acceptable  result,  since  mistakes  in 
spelling  and  in  form  of  letters  are  less  likely  to  occur. 

Repair  of  Slides.  The  cracking  of  the  glass  of  a  lantern  slide 
usually  occurs  in  the  cover  glass,  not  in  the  photographic  plate. 
Slit  the  binding  strip  around  the  edge,  throw  away  the  cover  glass 
and  substitute  another  which  has  been  cleaned  with  alcohol  and 
polished  with  a  chamois  or  piece  of  newspaper;  rebind  with  a  new 
strip  of  gummed  paper.  If  the  photographic  plate  is  broken,  it  is 
better  not  to  attempt  repair  upon  a  rented  slide.  If  you  own  the 
slide,  it  may  be  repaired  as  follows:  Place  the  broken  parts  glass  down 
ufon  a  cover  glass  and  cement  them  to  it  and  to  each  other  unth  Canada 
balsam  thinned  with  a  little  turpentine,  leaving  them  until  well  set. 
Then  cover  and  bind;  if  too  thick  for  the  slide  carrier,  project  without 
cover  glass. 


73 


TWO  SCENES  FROM  PHOTOPLAY,  "HER  MASTER' 
Courtesy  of  Sclig  Polyscope  Co.,  Inc.,  Chicago 


SCEITE  FROM  PHOTOPLAY,   "THE  FAIR  DENTIST' 

Courtesy  of  Independent  Moving  Pictures  Co.,   New  York 


MOTION  HEAD 

PART  I 


PORTRAYAL  OF  MOTION 

Abstractly  considered,  apart  from  the  means  for  projecting  it 
and  from  the  means  for  recording  it,  the  motion  picture  is  a  picture 
in  which  motion  is  the  prime  feature.  It  is  a  picture  so  recorded 
that,  itself  a  record  of  a  moving  thing  or  set  of  things,  it,  when 
properly  viewed,  will  reproduce  to  the  viewing  person  not  only  the 
outlines  and  details  of  the  objects  pictured  but  also  the  motion  of  the 
objects  pictured. 

A  running  horse  portrayed  by  a  fixed  picture,  such  as  a  lantern 
slide  or  fixed  print,  will  show  the  outlines  of  the  horse  in  full  detail 
in  the  properly  lighted  portions  of  the  animal  and  of  the  background; 
it  even  will  suggest  motion,  by  reason  of  the  position  in  which  the 
animal  is  portrayed,  perhaps  with  two  feet  off  the  ground  or  even 
galloping  with  all  four  feet  clear  of  the  earth;  but  in  such  a  picture 
the  motion  is  only  suggested  by  the  attitude  portrayed  by  the  still 
picture.  The  motion  picture  must  do  more  than  merely  suggest 
the  motion  of  the  subject  photographed;  it  actually  must  show  the 
motion  so  that  there  is  no  doubt  in  the  spectator's  mind  that  the 
object  being  exhibited  is  in  motion,  or  was  in  motion  at  the  time  it 
was  photographed.  Yet  the  motion  picture  in  itself  is  a  dead,  inert 
photograph.     How,  then,  is  motion  portrayed  in  it? 

Go  back  to  the  thought  of  motion  in  the  subject  itself.  In 
what  way  is  motion  manifested  to  the  spectator  viewing  the  sub- 
ject? The  movement  of  the  subject  is  known  only  by  observing  it 
twice  arid  noticing  whether  it  ii  or  is  not  in  the  same  place  or  position 
both  times.  If  it  is  in  the  same  place  both  times  it  is  observed,  then 
we  say  that  the  subject  is  still.  If  it  is,  upon  a  second  look,  in  a 
position  or  location  different  from  that  of  the  first  look,  the  ob- 
server says  that  the  subject  has  moved.  Now  looking  a  third  and 
fourth  time,  and  noting  that  each  time  the  subject  is  in  a  different 

Copyright,  1911,  by  American  School  of  Correspondence. 


75 


2  THE  MOTION  PICTURE 

position  from  any  of  the  other  positions  which  it  has  held,  the  ob- 
server says  that  the  subject  is  moving  continuously,  and  if  the  dif- 
ferences are  all  the  same,  and  if  we  have  looked  at  regular  intervals, 
the  observer  concludes  that  the  subject  is  moving  at  a  uniform  rate. 

Looking  at  a  thing  several  times  to  see  whether  it  is  moving  is 
an  act  performed  unconsciously.  The  eye  cannot  look  at  anything 
for  less  than  one-fiftieth  of  a  second,  because  of  a  peculiar  property 
of  the  eye- called  "persistence  of  vision,"  and  when  anything  is  seen 
in  any  position,  it  is  seen  for  that  length  of  time.  If  it  is  not  looked 
at  longer  than  that,  the  impression  of  motion  is  not  given.  Looking 
at  it  for  half  a  second,  it  is  seen  successively  in  twenty-five  different 
positions,  or  the  equivalent,  and  when  the  observer  looks  at  an  ob- 
ject for  half  a  second  to  see  whether  it  is  moving,  and  finds  that  it 
is  moving,  he  really  has  looked  several  short  looks  joined  each  after 
another,  and  in  each  of  the  brief  looks  the  object  has  been  in  a  dif- 
ferent position  from  that  of  the  preceding  look;  proof  of  motion  thus 
has  been  received. 

Proof  of  Motion.  Proof  of  motion  is  conclusive  to  the  human 
mind  when  upon  looking  continuously  at  a  physical  object  in  nature 
it  is  observed  to  change  its  position.  Proof  of  motion  in  the  subject 
of  a  picture  may  be  offered  by  the  same  means  of  making  it  apparent 
to  the  eye;  that  is,  while  the  eye  is  looking  continuously  at  the 
subject  portrayed  in  the  picture  the  subject  is  observed  to  change  its 
position  in  the  picture. 

A  series  of  pictures  may  be  made  with  a  single  camera,  which, 
by  close  notice,  will  prove  motion.  Assume  that  an  amateur  photog- 
rapher with  a  hand  camera  is  taking  pictures  as  rapidly  as  his  skilled 
hands  will  enable  him,  the  subject  being  a  parade  passing  down  a 
city  street.  The  camera  worker  is  situated  on  one  side  of  the  street 
opposite  a  prominent  building,  of  which  the  two  corners  and  the 
central  door  may  be  seen  in  each  picture  made  of  the  procession. 
When  these  pictures  are  developed  and  printed,  it  is  noted  that  in  one 
picture  a  carriage  drawn  by  distinctive  white  horses  is  seen  at  the 
right  of  the  picture,  apparently  entering  the  picture,  judging  from  the 
attitude  of  the  horses  and  the  direction  of  their  heads.  This  sug- 
gests motion,  but  does  not  prove  it.  Another  picture,  however, 
shows  the  horses  half-way  between  the  corner  of  the  building  and 
the  central  door;  another  picture  shows  the  horses  opposite  the  door 


76 


I 


MOTION  HEAD  3 

of  the  building,  with  the  carriage  still  close  behind;  still  another  pic- 
ture shows  the  horses  near  the  left  of  the  picture,  with  the  carriage 
close  behind  and  the  heads  of  the  horses  still  toward  the  left.  By 
comparing  these  pictures,  the  thoughtful  observer  will  conclude, 
and  correctly,  that  the  horses  and  the  carriage  were  moving 
while  the  series  of  pictures  was  being  taken. 
These  pictures,  when  taken  together  as  a 
series,  are  pictures  of  motion  and  show 
motion  if  one  studies  to  see  it.  The 
modern  perfected  motion  picture  is  but  the 
elaboration  of  this  method  of  recording 
motion,  and  the  projected  motion  picture 
is  but  a  perfected  method  of  viewing  it. 

Perfected  Motion  Picture.  The  per- 
fected motion  picture  makes  a  series  of 
pictures  similar  to  the  series  of  the  proces- 
sion, but  makes  them  so  rapidly  one  after 
another,  with  such  a  short  space  of  time 
between  pictures,  that  the  change  or 
difference  between  pictures  is  very  small, 
the  motion  being  shown  by  increments 
from  picture  to  picture.  Take  fur  example 
the  motion  picture  of  Fig.  1 ,  which  shows  a 
harvesting  machine  or  reaper  cutting  grain 
in  the  field.  One  part  of  such  a  machine 
is  a  large  revolving  flail,  comprising  a 
wheel-like  formation  of  six  or  eight  slats 
revolving:  over  the  sickle  or  cutting  bar  to 
prevent  the  cut  stalks  of  grain  from  falling 
forward  and  to  control  their  fall  backward 
over  the  sickle  bar.  This  wheel  of  slats 
revolves  rapidly  as  the  reaper  is  driven 
across  the  field,  cutting  the  grain.  Note 
the  picture  for  the  motion  of  the  slats.  In  the  top  picture,  the 
slat  next  the  top  reaches  to  the  driver's  hat  and  is  exactly  in 
line  with  the  brim  of  the  hat.  In  the  picture  next  to  the  top  figure, 
taken  only  one-fourteenth  of  a  second  later  in  time,  the  slat  is  not 
seen  at  the  brim  of  the  driver's  hat  but  noticeably  above  the  brim, 


Fi! 


;.    I.       Motion-Picture  of 
Harvesting  Machine  in 
Operation 


77 


4  THE  MOTION  PICTURE 

and  much  nearer  the  top  slat,  for  the  top  slat  is  descending.  In  the 
third  picture,  the  slat  being  watched  is  as  high  as  the  top  of  the 
driver's  hat  and  is  higher  than  the  slat,  formerly  the  top  slat  and 
now  going  down.  In  the  fourth  picture  of  the  series  the  slat  being 
watched  is  slightly  above  the  height  of  the  driver's  hat.  In  the  fifth 
picture,  taken  about  a  quarter  of  a  second  after  the  first  picture,  the 


Fig.  2.     Motion-Pictiu"e  Portrait  of  a  Lady 


slat  being  watched  has  reached  nearly  its  full  elevation  at  the  top  of 
the  wheel,  and  the  next  slat  has  reached  the  height  of  the  driver's 
shoulder.  In  the  sixth  and  last  picture  of  the  series,  the  slat  has 
moved  from  the  driver's  shoulder  to  the  height  of  his  chin.  Also 
note  the  position  of  the  driver.  In  the  first  picture,  not  all  of  his 
body  is  in  the  picture;  in  the  second,  it  is  all  in  the  picture;  in  the 
third,  there  is  a  space  between  his  body  and  the  margin  of  the  pic- 
ture; in  the  fourth,  the  space  is  wider;  and  in  the  fifth  and  sixth, 
the  space  between  driver  and  edge  of  picture  continues  to  widen. 

In  Fig.  2,  a  motion  picture  is  shown  of  circular  form  instead  of 
strip  film  form.     In  this  figure,  it  may  be  determined  by  studying 


78 


J 


MOTION  HEAD 


the  small  pictures  in  sequence  that  the 
lady  begins  and  ends  the  picture  with  a 
profile  view,  but  turns  her  full  face  toward 
the  camera  during  the  progress  of  the 
picture,  also  she  raises  her  hands  to  her 
head  as  though  arranging  her  hair. 

In  both  Fig.  1  and  Fig.  2,  the  differ- 
ence between  any  two  consecutive  pictures 
is  so  small  that  the  pictures  are  alike 
except  upon  the  closest  inspection. 

In  taking  pictures  of  objects  which 
are  in  motion  at  such  speeds  as  the  eye  can 
follow  easily,  and  where  the  desire  is  to 
reproduce  the  motion  pretty  much  as  it 
was  seen  by  the  eye  when  viewing  the 
physical  object,  an  interval  of  about  one- 
fourteenth  of  a  second  is  taken,  the  object 
being  photographed  at  the  end  of  each 
one-fourteenth  second,  as  is  the  case  with 
the  harvesting  machine.  In  the  case  of 
motions  which  are  so  slow  that  the  eye  with 
ordinary  observation  cannot  notice  the 
motion,  a  longer  interval  of  time  is  con- 
veniently taken.  A  growing  plant  may  be 
photographed  once  each  day,  and  not 
oftener  than  once  each  hour  unless  it  is 
desired  to  portray  the  opening  of  a  single 
blossom;  with  these  pictures  taken  at  these 
comparatively  long  intervals,  the  change 
between  successive  pictures  will  be  very 
small.  In  the  case  of  motions  which  are 
so  fast  that  the  eye  cannot  follow  the 
motion,  a  much  shorter  interval  of  time 
must  be  taken,  in  order  that  the  change 
in  the  position  of  the  moving  object  in 
successive  pictures  will  be  very  small.  The 
wings  of  an  insect  in  flight  move  so  rapidly 
that  to  the  eye  they  are  but  a  blur,  and  to 


Fig.  3.     Motion  Picture  of  an 
Insect,  Made   at  High   Speed 


79 


6  THE  MOTION  PICTURE 

photograph  them  in  a  manner  that  will  reveal  their  proper  motions 
for  study  requires  that  they  be  photographed  at  much  shorter  inter\'als 
than  one-fourteenth  of  a  second.  Pictures  of  this  class  have  been 
taken  at  the  rate  of  two  thousand  pictures  in  one  second.  Fig.  3 
shows  such  a  picture,  the  subject  being  a  dragon-fly  in  full  flight. 
Motion  pictures  of  bullets  in  flight  have  been  taken  at  the  rate  of 
five  thousand  pictures  in  a  single  second. 

This  is  the  motion  picture — a  picture  which  shows  a  record  of 
the  successive  positions  taken  by  a  moving  object  in  successive  in- 
tervals of  time.  AMiether  the  picture  takes  the  form  of  pictures  in 
a  row  upon  a  transparent  celluloid  strip,  as  the  original  of  Fig.  1, 
or  whether  it  takes  the  form  of  a  spiral  line  on  a  souvenir  postcard, 
or  whether  the  successive  pictures  were  taken  at  the  rate  of  fourteen 
per  second,  fourteen  per  year,  or  fourteen  in  one-hundredth  of  a 
second,  all  is  immaterial,  since  in  any  of  the  cases  the  fundamental 
requirement  is  fulfilled  and  it  is  a  picture  of  motion. 

Viewing  Devices.  The  perfected  projecting  machine  is  but  one 
form  of  viewing  device.  Just  hold  a  slip  of  white  paper  above  the  film 
gate  and  watch  the  picture  film  as  it  enters  the  gate;  the  full  motion 
of  the  drama  takes  place  there.  The  intermittent  mechanism  pre- 
sents picture  after  picture  at  regular  and  proper  speed,  and  the  mo- 
tion of  the  picture  is  seen  without  projection. 

With  the  card  of  Fig.  2,  the  method  of  viewing  is  entirely  differ- 
ent. The  card  is  placed  upon  a  light  carrier,  similar  to  the  disk  of  a 
talking  machine  using  the  flat  type  of  record;  an  eyepiece  is  con- 
veniently placed,  and  as  the  disk  of  the  picture  revolves  with  a  step- 
by-step  movement,  the  eyepiece  moves  across  as  the  reproducer 
needle  of  the  talking  machine  does.  Thus  the  pictures  are  seen  in 
order.  By  taking  a  transparent  print  from  the  negative,  projection 
upon  a  small  scale  may  be  accomplished. 

With  the  picture  strip  of  Fig.  1,  it  is  necessary  only  to  see  the 
pictures  successively,  and  preferably  for  ordinary  scenes  to  view  them 
in  succession  at  the  same  speed  that  they  were  taken  by  the  camera. 
To  do  this,  some  device  is  required  to  take  away  the  first  picture  and 
substitute  the  second  picture,  then  to  take  away  the  second  picture 
and  substitute  the  third,  and  so  on  indefinitely,  that  all  of  the 
pictures  of  the  series  may  be  \newed  by  looking  at  the  same  viewing 
position,  as  by  looking  at  a  screen  upon  which  the  pictures  are  pro- 


80 


MOTION  HEAD  7 

jected  in  rapid  succession.  Further,  to  attain  the  ilhision  of  motion 
in  the  picture,  the  spectator  should  be  deceived,  if  possible,  into  be- 
lieving that  he  is  looking  at  the  same  picture  all  of  the  time,  at  least 
in  so  far  as  the  fixed  objects  of  the  picture  are  concerned.  This  illu- 
sion can  be  obtained  by  making  the  shift  from  one  picture  to  another 
imperceptible  to  the  spectator,  which  is  done  by  making  the  time  of 
shift  as  brief  as  possible,  bringing  it  at  least  reasonably  near  to 
the  limits  of  persistence  of  \nsion. 

Persistence  of  Vision,  The  human  eye  does  not  see  an  object 
instantaneously.  Time  is  required  for  the  muscles  and  nerves  to 
act.  ^^^lat  length  of  time  is  required  by  the  eye  and  brain  to  ap- 
preciate a  view  after  the  light  has  fallen  upon  the  lens  of  the  eye 
has  not  been  recited,  nor  has  it  been  told  w^hat  length  of  time  is  re- 
quired for  the  eye  to  cease  seeing  the  vision  after  the  light  has 
ceased  to  fall  upon  the  lens,  for  the  eye  is  slow  about  quitting  as 
well  as  beginning;  but  it  has  been  established  that  the  eye  seems  to 
see  any  view  probably  [one-fiftieth  of  a  second  longer  than  light 
actually  falls  upon  the  lens  of  the  eye  This  action  of  the  human 
eye  is  called  by  the  name,  "persistence  of  vision,"  because  vision 
seems  to  remain  or  persist  in  action  after  the  thing  viewed  actually 
has  vanished. 

One  effect  of  the  persistence  of  vision  is  that,  when  two  views  are 
seen  with  an  inter\'al  of  not  more  than  one-fiftieth  second  between  the 
two,  the  eye  blends  the  two  and,  therefore,  does  not  appreciate  the 
interval  of  darkness  which  has  occurred  between  the  two.  If  the 
pictures  are  entirely  unlike,  there  is  a  blur  of  confusion  of  the  two. 
If  the  pictures  are  alike  in  some  details  and  different  in  other  details, 
then  it  seems  to  the  eye  that  the  similar  details  have  not  changed 
and  that  the  unlike  details  have  changed. 

In  the  dissolving  lantern,  with  two  views  showing  a  different  use 
of  figures  before  the  same  background  or  scene  setting,  skilfully 
dissolved,  it  seems  to  the  spectator  that  the  background  details  have 
not  changed,  that  the  same  picture  has  been  viewed  continuously, 
but  that  the  figures  of  the  picture  alone  have  changed  their  pose. 

In  the  series  of  photographs  of  the  procession  studied  as  an 
example,  it  was  by  the  comparison  of  a  moving  object  with  a  fixed 
object  in  the  picture  that  motion  in  the  fixed  object  was  proven.  In 
the  same  manner,  it  is  by  comparison  of  moving  and  fixed  objects 


81 


8  THE  MOTION  PICTURE 

in  the  projected  motion  picture  that  motion  of  the  actors  is  made  so 
realistic  and  so  natural  in  its  execution  that  it  seems  a  reproduction 
of  true  hfe  and  the  spectator  is  brought  to  realize  that  he  is  watching 
a  picture  of  motion  rather  than  a  picture  of  inanimate  things,  or  a 
picture  in  which  motion  is  merely  suggested  as  an  art  or  trick  or 
device.  To  secure  this  illusion,  the  fixed  objects  of  the  picture  must 
remain  absolutely  motionless  upon  the  picture  screen. 

With  the  perfected  motion  pictures  and  motion-projecting  ma- 
chine, exactly  the  illusion  of  the  dissolving  lantern  is  desired.  Two 
successive  pictures  must  be  projected  with  such  skill  that  the 
spectator  is  deceived  into  believing  that  he  is  looking  at  a  single 
picture  of  a  scenic  setting  or  fixed  objects  of  the  picture,  and  that, 
watching  a  single  picture,  the  moving  objects^  have  changed  their 
positions. 

jNIany  projecting  devices  embodying  the  principle  of  I  he  dis- 
solving lantern — namely,  the  principle  of  projecting  the  second  pic- 
ture before  the  first  picture  is  t;iken  away  and  then  of  projecting 
the  third  picture  before  the  second  picture  is  taken  away,  and  so  on 
through  the  series — have  been  suggested  and  some  of  them  have  been 
operated  successfully.  However,  the  projecting  device  which  has 
come  into  general  use  depends  upon  the  phenomenon  of  the  per- 
sistence of  vision  to  smooth  over  the  change  from  picture  to  picture, 
the  change  being  made  so  quickly  and  so  smoothly  that  the  human 
eye  cannot  detect  the  coming  of  the  new  picture  or  the  going  of  the 
old,  nor  guess  at  the  interval  of  darkness  or  of  blur  which  occurs 
between  the  two. 

Projection  by  Persistence  of  Vision.  The  method  of  projection 
which  takes  advantage  of  the  persistence  of  vision  fills  the  require- 
ments of  the  case  entirely  and  is  entirely  satisfactory  when  well  done. 
Its  theory  is  that  the  first  picture  may  be  shown  upon  the  screen,  that 
the  first  picture  may  be  cut  off  from  the  screen  by  a  shutter,  that  the 
film  may  be  shifted  to  bring  the  second  picture  in  position  for  pro- 
jection, and  that  the  shutter  may  be  removed  to  permit  the  projec- 
tion of  the  second  picture,  all  in  a  space  of  darkness  upon  the  screen 
so  brief  that  the  first  picture  projected  will  persist  in  the  vision  of  the 
spectator  until  the  change  in  the  motion  head  has  been  made  and 
the  second  picture  is  upon  the  screen,  when  the  spectator  will  see  the 
fixed  objects  of  the  view  in  their  places  in  the  second  picture  as  in  the 


R2 


MOTION  HEAD  9 

first,  with  the  moving  objects  of  the  view  changed  to  their  next  po- 
sition, whereby  the  spectator  beUeves  that  he  has  had  continuous 
vision  and  believes  that  the  fixed  objects  have  been  upon  the  screen 
in  fixed  position  all  the  time,  and  that  the  moving  objects  also  have 
been  upon  the  screen  all  of  the  time  but  that  they  have  moved  upon  the 
screen  to  the  new  position.  In  the  same  manner,  the  second  picture 
persists  in  the  vision  of  the  spectators  until  the  dark  interval  is  over 
and  the  shift  has  been  made  and  the  third  picture  is  projected;  the 
third  picture  persists  until  the  fourth  picture  is  projected,  and  so 
indefinitely  until  the  picture  is  out,  retaining  all  fixed  objects  in  con- 
tinuous and  stationary  vision  before  the  spectator  by  the  phenomenon 
of  persistence  of  vision  and  showing  the  motion  of  all  moving  objects 
in  the  successive  pictures,  the  pictures  showing  so  small  an  amount  of 
movement  between  successive  pictures  that  the  motion  seems  smooth 
and  continuous  and  not  jerky  step-by-step  projection  which  it  really 
is.  That  jerkiness,  by  the  art  of  the  film  maker  and  assisted  by  the 
art  of  the  projection  operator,  must  be  smoothed  out. 

Motion  Mechanism.  The  slowest  speed  at  which  it  has  been 
found  practicable  to  project  a  series  of  images  having  ordinary  motion, 
as  of  actors  walking,  and  to  smooth  out  the  jerkiness  which  would  be 
expected  by  the  step-by-step  nature  of  the  projection  when  the  persist- 
ence-of-vision  method  is  used,  is  about  fourteen  pictures  per  second. 
Fourteen  pictures  are  to  be  projected  each  second,  and  with  uniformity. 
To  expect  the  operator  to  make  fourteen  shifts,  or  fourteen  voluntary 
motions  resulting  in  shifts,  each  second,  as  in  changing  lantern 
slides,  and  to  do  it  with  regularity,  is  quite  an  impossible  require- 
ment, so  a  machine  has  been  devised  for  doing  the  shifting  in  an 
automatic  manner,  at  regular  interv^als,  the  length  of  the  intervals 
depending  only  upon  the  speed  at  which  the  machine  is  driven. 

^Vhen  driven  by  an  electric  motor — a  great  convenience  in  some 
ways  but  a  very  great  disadvantage  in  other  ways — the  entire  op- 
eration is  quite  automatic,  it  being  necessary  only  for  the  operator 
to  adjust  and  start  the  machine  and  the  projection  of  motion  for 
some  twenty  minutes  follows,  presumably  in  an  entirely  satisfactory 
manner  if  the  preliminary  adjustments  have  been  perfect,  ^^^len 
not  driven  by  a  motor,  the  operator  is  provided  with  a  crank,  which 
is  turned  at  a  constant  speed,  and  which  results  in  the  automatic 
shifting  being  performed  under  the  driving  power  of  the  crank  handle. 


83 


10  THE  MOTION  PICTURE 

The  automatic  shifting  device  is  called  a  motion  head,  and  it 
replaces  in  functions  only  the  slide  holder  of  the  lantern,  all  the  other 
portions  of  the  fixed  optical  lantern  being  retained.  All  the  features 
of  the  optical  lantern  for  song  slides  are  retained  in  use  with  the  mo- 
tion head  except  the  projecting  or  objective  lens,  a  special  lens  for 
the  motion  pictures  being  carried  upon  the  motion  head  itself. 

OPTICAL  SYSTEM  FOR  MOTION  PICTURES 

The  optical  system  of  the  motion-picture  lantern  adds  to  the 
system  of  the  stereopticon,  two  shutters,  an  intermittent  shutter  and  a 
fire  shutter.  Because  of  the  short-focus  lens  required  for  the  greater 
magnification  of  the  motion-picture  image  as  compared  with  the  fixed 
lantern  slide,  the  motion-picture  image  or  film  strip  of  images  is  placed 
farther  awav  from  the  condensers  than  is  the  fixed  slide.  AVith  these 
two  modifications,  the  two  optical  systems  cease  their  differences,  and 
the  fundamental  principles  of  one  are  the  fundamental  principles -of 
the  other.  The  arrangement  of  elements  for  the  motion-picture  sys- 
tem is  shown  in  its  usual  form  in  Fig.  4,  the  picture  screen  or  viewing 
screen,  which  would  be  located  properly  far  to  the  right,  being 
omitted  from  the  picture  in  order  that  all  the  other  elements  might 
be  drawn  to  a  larger  scale,  more  clearly  and  distinctly. 

Lamp.  As  has  been  described  under  the  discussion  of  the 
optical  lantern  for  fixed  slides,  the  motion-picture  arc  lamp  is  of 
maximum  strength,  giving  a  very  strong  light  and  a  very  intense 
heat,  such  as  is  suitable  for  the  motion  picture  alone,  and  unsuit- 
able for  the  lantern  sHde. 

Condensers.  The  condensers  are  the  same  as  used  for  the 
optical  lantern  for  fixed  slides,  and  are  the  same  condensers,  being 
carried  by  the  lamp  house  from  the  motion  head  to  the  stereo  lens, 
and  again  from  the  stereo  lens  to  the  motion  head,  but  where  the 
requirements  for  condensers  for  the  motion  head  differ  in  any  way 
from  the  requirements  for  the  fixed  lantern  slides,  the  motion  head 
should  be  given  preference.  Proper  instructions  for  the  adjustment 
of  the  condensers  for  the  motion  head  are  repeated  here,  as  though 
they  were  to  be  used  for  the  motion-head  work  alone. 

Back  Condenser.  This  is  the  condenser  at  the  left  in  the  dia- 
gram, next  to  lamp  L.  It  is  shown  in  the  diagram  as  the  thicker 
of  the  two  condenser  glasses,  and  usually  is  so  in  practice.     The 


84 


MOTION  HEAD 


11 


focal  length  may  he  as  short  as  4^  inches.  Its  length  of  focus  governs 
the  distance  of  the  lamp  L  from  the  back  surface  of  the  glass,  and 
its  length  of  focus  in  turn  is  controlled  to  some  extent  by  the  size 
of  the  lamp  house,  since  the  back  condenser  must  take  the  rays  of 
the  lamp  from  a  lamp  position  within  the  limiting  range  of  move- 
ment permitted  by  the  lamp  house.  INIost  lamp  houses  will  permit 
the  use  of  back  condensers  4  to  8  inches  focal  length. 


Fig.  4.     Optical  System  for  Motion-Picture  Projection 

A — Feed  Reel;  B — Upper  Steady  Sprocket,  or  Top  Feed:  C — Condenser  Case  and 
Condenser  Glasses;  b — Presser  Roller  and  .\mi  for  Top  Feed;  G — Film  Gate;  H — Tension 
Plate  for  Film  Gate;  K — Intermittent  Shutter,  Barrel  Type;  L — Lamp,  or  Point  of  Loca- 
tion of  Arc;  M — intermittent  Sprocket;  .V — Fii'e  Shutter  or  Safety  Shutter;  O — Objective 
Lens  or  Projection  Lens;  P — Presser  Roller  and  Arm  for  Intermittent  Sprocket;  S — 
Film  in  Film  W'indow  or  Apertiu-e  of  Film  Gate;  .S" — Film  leaving  Intermittent  Sprock- 
et to  Basket.  The  dotted  lines  represent  the  outer  rays  of  the  beam  of  light,  and  pass 
to  the  right  to.the  Picture  Screen,  which  is  not  shown  in  the  figure. 

The  shorter  the  length  of  focus  of  the  back  condenser,  the  thicker 
will  be  the  glass  in  the  middle  and  the  closer  must  be  the  lamp  L, 
consequently  the  greater  the  heat  upon  the  surface  of  the  glass; 
incidentally,  also,  the  brighter  the  light  upon  the  picture  screen. 
On  the  contrary,  with  a  condenser  of  longer  focus,  the  glass  will,  be 
thinner  in  the  middle,  and  will  be  farther  away  from  the  lamp,  thus 
lessening  the  danger  of  breaking  the  glass.  Incidentally,  also,  the 
less  light  will  fall  upon  the  condenser  and,  therefore,  the  less  light 
will  there  be  upon  the  picture  screen. 

The  length  of  focus  of  the  back  condenser  may  be  considered 
a  compromise  between  the  strength  of  the  light  on  the  screen  and 


85 


12  THE  :\IOTIOX  PICTURE 

the  risk  of  condenser  breakage.  Any  length  of  focus  within  wide 
limits — 4  to  8  inches,  or  in  a  large  lamp  house  even  much  more  than 
this — will  give  a  properly  distributed  lighting  of  the  screen,  varying 
in  brightness  according  to  the  length  of  focus  used. 

The  shorter  length  of  focus  for  the  back  condenser  will  require 
greater  skill  on  the  part  of  the  operator  in  keeping  the  light  in  focus. 
The  light  being  nearer,  a  slight  change,  say,  an  eighth  of  an  inch,  in 
the  position  of  the  arc,  will  make  more  difference  upon  the  picture 
screen  than  the  same  amount  of  change  would  make  with  a  con- 
denser of  longer  fgcus.  The  longer  focus  of  condenser  (thinner  glass) 
makes  the  lamp  much  easier  to  adjust  for  a  smooth,  evenly-lighted 
picture  screen  (provided  always  that  your  front  condenser  is  of 
proper  focal  length)  unless  the  back  condenser  happens  to  be  so 
long  in  focal  length  that  the  lamp  cannot  be  brought  far  enough  back 
in  the  lamp  house  for  it ;  such  a  condenser  is  too  long  for  the  lamp 
house,  and  good  projection  cannot  be  had  with  it.  Of  course,  some 
sort  of  quality  of  picture  can  be  thrown  upon  the  screen  with  it, 
but  it  makes  poor  projection. 

Front  Condenser.  This  is  the  condenser  at  the  right  in  the 
diagram,  the  outside  one  of  the  lamp  house.  It  is  shown  in  the 
diagram  as  the  thinner  of  the  two  condenser  glasses.  The  focal 
length  should  be  exactly  right  to  cause  the  rays  of  the  lamp  to  come 
to  a  focus  at  the  focal  center  of  the  objective  lens  0,  whose  position 
is  determined  by  adjusting  it  properly  in  focal  length  and  position 
in  the  motion-head  lens  mount  in  order  to  focus  the  picture  film 
S  properly  and  in  proper  size  upon  the  distant  picture  screen. 

Condensers  are  offered  by  all  supply  houses  in  lengths  which 
vary  by  1  inch,  usually  being  offered  in  4^,  5^,  6|,  and  7^  inches. 
They  may  be  obtained  from  the  makers  in  focal  lengths  of  4,  4^, 
5,  5i  6,  6i  7,  7i  8,  8i  9,  9^,  10,  10^  11,  and  12  inches.  In  addi- 
tion, they  may  be  made  to  order  of  any  length  called  for. 

With  a  9  by  12  foot  picture  at  a  50-foot  throw,  an  objective 
lens  at  O  having  a  focal  length  of  about  4  inches  would  be  required. 
In  connection  with  this  there  would  be  required  for  the  lantern  slides 
a  stereo  lens  having  a  focal  length  of  about  12  inches.  With  a  differ- 
ence of  8  inches  between  the  two  lenses,  the  distance  from  the  lan- 
tern slide  in  its  carrier  to  the  motion-picture  film  in  its  gate  .should 
be  about  8  inches,  equal  to  the  difference  between  the  lens  lengths 


86 


MOTION  HEAD  13 

Taking  the  motion  head  as  it  stands  on  the  table,  the  length  of 
the  front  condenser  is  calculated  in  either  case  by  simple  addition. 
The  focal  length  of  the  motion-picture  lens  is  added  to  the  distance 
from  the  film  in  its  gate  to  the  middle  of  the  condenser  box.  In  the 
instance  taken,  of  a  4-inch  lens,  with  8  inches  from  the  film  to  the 
slide  position  and  another  2  inches  back  to  the  middle  of  the  con- 
denser box,  it  gives  a  total  length  of  14  inches  for  the  focal  length  of 
the  front  condenser.  Tliis  is  the  limit.  A  condenser  longer  than 
14  inches  will  not  give  as  good  projection  as  one  shorter;  the  front 
condenser  should  be  14  inches  focal  length  or  shorter. 

Condensers  as  a  Pair.  The  condenser  glasses  should  not  be  of 
too  great  difference  in  focal  length,  as  the  lamp  adjustments  again 
become  difficult,  and  are  easier  with  the  condensers  more  nearly 
of  equal  lengths.  For  the  maximum  illumination  in  the  instance 
considered,  a  50-foot  throw  and  a  4-inch  lens,  with  14  inches  from 
center  of  condensers  to  center  of  lens,  the  theoretical  focal  lengths 
required  would  be  a  5-inch  glass  for  the  back  and  a  14-inch  glass 
for  the  front.  This  combination  gives  an  equivalent  focal  length  of 
about  4|  inches  for  the  pair  of  glasses.  About  the  same  equivalent 
length  for  the  pair  of  glasses  would  be  obtained  by  the  combina- 
tion of  a  57-inch  glass  and  a  10^-inch  glass,  by  the  combination  of 
a  6-inch  glass  and  a  9-inch  glass;  by  the  combination  of  a  C^-inch 
glass  and  an  8-inch  glass;  or  by  the  combination  of  two  7-inch  glasses. 
Of  these  combinations,  the  5  and  14  combination  would  be  the 
hardest  to  work  in  practice  but  would  be  productive  of  the  best 
results  when  properly  worked  by  the  skilled  operator.  The  7  and 
7  combination  will  not  give  good  results  with  any  amount  of  skill 
on  the  part  of  the  operator.  The  best  combinations  to  use  are  the 
6  and  9  or  the  5^  and  lOi;  the  latter  is  better  if  the  glasses  can  be  ob- 
tained, and  its  use  lies  well  within  any  careful  operator's  skill. 

Another  consideration  is  the  limits  of  the  cone  of  light  -iis  deter- 
mined  in  dimensions  by  the  position  of  the  optical  center  of  the  motion- 
picture  objective  lens  and  the  sides  of  the  film-gate  window.  This 
must  not  be  larger  at  the  condenser  than  the  face  of  the  condenser 
glass.  In  the  instance  assumed,  the  diagonal  of  the  f  by  1-inch  film- 
gate  window  is  just  Ij  inches,  and  its  distance  from  the  optical  center 
of  the  lens  is  about  4  inches  (4.007"),  while  the  distance  from  the 
optical  center  of  the  Ipus  to  the  condenser  face  is  about  13  inches. 


87 


14  THE  MOTION  PICTURE 

By  the  proportion,  4:  I3  :  :  13  :A,  where  A  is  the  diagonal 
of  the  cone  upon  the  condenser  face,  a  vahie  of  4  inches  for  the 
dimension  A  is  obtained,  which  is  easily  cared  for  by  the  usual  con- 
denser of  4J  inches  diameter  of  face  when  the  condensers  are  of 
proper  focal  length  and  the  lamp  is  properly  adjusted. 

^\^len  the  cone,  formed  l)y  the  limits  of  the  optical  center  of 
the  lens  and  the  corners  of  the  film  aperture,  falls  outside  of  the 
front  condenser  surface,  the  corners  of  the  pictures  on  the  screen 
will  be  dark.  The  remedy  is  to  move  the  motion  head  as  a  whole 
nearer  to  the  condensers,  even  though  this  change  should  bring  the 
focal  center  of  the  motion-picture  lens  nearer  to  the  condensers 
than  the  focal  center  of  the  lantern  slide  lens,  and  thereby  require 
a  change  from  the  motion  head  to  the  stereo  lens,  or  back. 

For  the  best  lighting  of  the  screen,  the  front  condenser  should 
be  as  long  as  possible,  but  should  be  a  little  shorter  than  the  limit, 
since  the  exact  limit  is  hard  for  the  operator  to  work  satisfactorily, 
and  a  condenser  a  little  too  long  is  much  worse  for  the  picture  than 
one  a  Httle  too  short. 

Short  Rules  for  Condenser  Lengths.  The  front  condenser  glass 
ihall  have  a  focal  length  two  inches  less  than  the  distance  from  the  middle 
of  the  condenser  hox  to  the  middle  of  the  7nct  ion -picture  objective  lens. 
The  hack  condenser  should  he  five  and  one-half  'inches  in  focal  length. 

The  hack  condenser  may  he  four  and  one-half  inches  to  force  the 
light  upon  the  picture  screen  at  the  risk  cf  breaking  more  condensers. 

The  hack  condenser  may  he  six  and  one-half  inches  to  reduce 
the  breakage  of  condensers  at  the  cost  cf  a  slight  reduction  cf  the 
brightness  of  the  picture  screen. 

When  the  front  condenser  is  too  short,  the  correction  cannot  he 
accomplished  by  suhstituti)ig  the  back  glass  with  one  a  little  longer. 

Use  the  longest  focal  length  {the  thinnest  glass)  for  the  front 
glass  of  the  condensers. 

Lenses.  The  motion-picture  lens  is  similar  to  the  stereopticon 
or  fixed  picture  lens  in  all  respects  except  in  that  of  focal  length. 
It  is  similar  in  focal  length,  too,  so  far  as  the  fundamental  principles 
of  projection  are  concerned,  and  its  focal  length,  size  of  picture  pro- 
duced, and  required  length  of  throw  may  be  determined  by  the  rules, 
both  for  approximation  and  exactness,  which  have  been  given  in 
connection  with  the  discussion  of  lenses  for  stereopticon  work. 


88 


MOTION  HEAD 


15 


TABLE  I 
Showing  Size  of  Screen  Image  Wiien  Moving  Picture  Films  Are 

Projected 

Size  of  Mask  Opening  IJ  by  Jg  inch 


Equiv. 
Focus 
Inches 

15 

20 

25 

30 

35 

40 

45 

50 

60 

70 

80 

90     100 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft. 

ft.      ft. 

2J- 

4.8 

6.4 

8.0 

9.6 

11.3 

12.9 

14.5 

16.1 

6.5 

8.7 

11.0 

13.2 

15.4 

17.6 

19.8 

22.0 

21 

5.4 

6.8 

8.2 

9.6 

10.9 

12.3 

13.7 

16.4 

7.4 

9.3 

11.2 

13.1 

14.9 

16.8 

18.7 

22.4 

3 

4.5 

5.7 

6.8 

8.0 

9.1 

10.3 

11.4 

13.7 

16.0 

6.2 

7.7 

9.3 

10.9 

12.4 

14.0 

15.6 

18.7 

21.8 

3* 

4.9 

5.8 

6.8 

7.8 

8.8 

9.8 

11.7 

13.7 

15.7 

6.6 

8.0 

9.3 

10.6 

12.0 

13.3 

16.0 

18.7 

21.4 

4 

42 

5.1 

60 

6.8 

7.7 

8.5 

10.3 

12.0 

13.7 

15.4 

5.8 

7.0 

8.1 

9.3 

10.5 

11.6 

14.0 

16.3 

18.7 

21.0 

H 

4.5 

5.3 

6.2 

6.8 

7.7 

9.1 

10.6 

12.2 

13.7 

15.4 

6.2 

7.2 

8.4 

9.3 

10.5 

12.4 

14.5 

16.6 

18.7 

21.0 

o 

4.8 

5.4 

6.1 

6.8 

8.2 

9.6 

10.9 

12.3 

13.7 

6.5 

7.4 

8.4 

93 

11.2 

13.0 

14.9 

16.8 

18.7 

5h 

4.3 

4.9 

56 

6.2 

7.4 

8.7 

9.9 

11.2 

12.4 

5.9 

6.7 

7.6 

8.4 

10.2 

11.9 

13.6 

15.3 

17.0 

6 

4.5 

51 

5.7 

6.8 

8.0 

9.1 

10.3 

11.4 

6.2 

7.0 

7.7 

9.3 

10.9 

12.4 

14.0 

15.6 

GV 

47 

5.2 

6.3 

7.3 

8.4 

9.6 

10.6 

6.4 

7.1 

8.6 

10.0 

11.4 

13.0 

14.5 

7 

4.4 

49 

5.8 

6.8 

7.8 

8.8 

9.8 

6.0 

6.6 

8.0 

9.3 

10.6 

12.0 

13.3 

~h 

4.5 
6.2 

5.4 
7.4 

6.4 

8.7 

7.3 
10.0 

8.2 
11.2 

9.1 
12.3 

8 

5.1 

7.0 

6.0 

8.1 

6.8 
9.3 

7.7 
10.5 

8.5 
11.6 

The  difference  between  the  size  of  the  lantern-slide  ^vindo^^'  or 
the  mask  window  of  the  slide,  and  the  motion-picture  window, 
must  be  borne  in  mind.  The  size  of  lantern  slide  usually  calculated 
for  in  computing  lens  dimensions  is  2f  inches  by  3  inches,  a  dimen- 
sion which  io  exceeded  in  many  slides.  In  the  matter  of  the  motion 
picture  as  commercially  used  in  the  theater,  the  size  of  the  window 
for  projection  is  called  |  inch  by  1  inch,  is  never  more  than  that, 
and  is  never  less  than  \l  ly  If  inch. 

The  projected  picture  of  the  motion-picture  film  always  is 
about  three-(juarters  as  high  as  it  is  wide,  and  this  proportion  must 


89 


16  THE  MOTION  PICTURE 

be  taken  into  consideration  when  calculating  upon  the  dimensions 
of  the  picture  which  is  to  be  thrown  upon  the  picture  screen. 

The  desirable  results  of  operating  lantern  slides  with  a  slide- 
carrier  window  mask  have  been  discussed  in  connection  with  the 
operation  of  the  optical  lantern  for  fixed  slides.  The  same  good 
results  are  obtained  in  motion  pictures  by  the  use  of  a  window  mask 
in  the  window  of  the  film  gate,  the  aperture  plate,  as  it  is  called,  hav- 
ing an  aperture  just  a  little  smaller  than  the  pictures  upon  the  film, 
so  that  the  side  lines  of  the  picture  upon  the  screen  are  formed  not 
by  the  film  picture  but  by  the  aperture  plate  of  the  motion  head. 
INIost  projecting  machines  are  equipped  with  an  aperture  plate  which 
"trims"  the  picture  jV  inch  all  around,  reducing  the  size  of  the  visible 
picture  to  y|  by  yf  inch. 

Table  I  gives  the  size  of  projected  picture  with  different  lengths 
of  throw  and  with  different  focal  lengths  of  projecting  lenses  with  an 
aperture  or  mask  opening  \l  by  y|  inch. 

At  the  left  in  the  first  column  is  given  the  lengths  of  the  lenses, 
from  2|  inches  to  8  inches,  for  which  the  table  is  computed.  The 
columns  at  the  right  of  the  first  column  are  arranged  for  the  different 
lengths  of  thrown  the  length  of  throw  considered  in  each  column 
being  mentioned  at  the  top  of  that  column. 

For  each  length  of  lens,  there  are  two  figures  in  the  columns 
for  length  of  throw.  These  two  figures  are  the  height  and  width 
upon  the  screen  of  the  projected  picture  which  will  be  secured  by 
using  the  length  of  lens  mentioned  at  the  left  of  the  pair  of  figures  and 
using  it  wdth  the  throw  mentioned  at  the  top,  above  the  pair  of  figures. 

From  Table  I  may  be  obtained: 

The  lens  length  required  to  give  a  desired  picture  when  the  throio 
is  known. 

The  size  of  'picture  which  will  he  given  by  any  certain  lens  when 
the  throw  is  known. 

The  length  of  throiv  to  be  taken  to  secure  a  picture  of  a  desired 
size  with  any  certain  lens. 

To  Take  Lens  Length.  Find  in  the  table  the  length  of  throw 
which  you  have.  This  will  be  found  as  the  number  of  feet  men- 
tioned at  the  top  of  one  of  the  columns.  Now  look  down  in  this 
column  until  a  pair  of  figures  is  found  givi'ng  the  size  of  picture  which 
you  desire  to  project.    AVhen  this  pair  of  figures  is  found,  lay  a  card 


00 


SCENE  FROM  PHOTOPLAY,  "THE  HERDERS" 

Courtesy  of  Selig  Polyscope  Co.,  Inc.,  Chicago 


MOTION  HEAD  17 

across  the  book  page,  even  with  the  lines  and  just  showing  above 
its  edge  the  pair  of  figures  showing  the  desired  size  of  picture  in 
the  proper  length  of  throw  column.  At  the  left  of  the  lens  table  and 
just  above  the  edge  of  the  card  will  be  the  length  of  focus  in  inches 
of  the  lens  required  for  that  size  of  picture. 

Example.  You  have  a  70-foot  throw,  and  desire  a  picture  about  12 
feet  wide.  Finding  the  column  marked  at  the  top  70  feet  and  looking  down 
that  column,  the  pair  of  figures,  8.7  by  11.9  is  found,  and  placing  a  card  on 
the  page  the  figure  5^  is  seen  at  the  left  above  the  edge  of  the  card.  An  ob- 
jective lens  of  5h  inches  equivalent  focal  length  -will  give  a  picture  about  8 
feet  9  inches  high  by  about  11  feet  10^  inches  wide. 

To  Take  the  Picture  Size.  Tn  this  problem,  you  have  the  lens 
which  you  are  thinking  of  using,  or  must  use,  and  you  have  the 
length  of  throw  over  which  it  must  be  used.  At  the  left  of  the  page, 
find  the  focal  length  of  the  lens  in  inches,  either  as  marked  on  the 
lens,  or  as  measured  as  described  for  stereo  lenses  for  the  optical 
lantern.  Place  a  card  across  the  page  just  below  the  figure  of  the 
length  of  lens,  so  that  the  card  will  show  above  its  edge  a  row  of  pairs 
of  figures  of  which  in  each  pair  the  lower  figure  of  the  pair  will  be 
the  larger  figure.  Now  find  the  length  of  throw  at  the  top  of  the 
narrow  columns,  and  under  that  length  and  at  the  edge  of  the  card 
will  be  found  the  pair  of  figures  which  tell  the  height  and  width  of 
the  projected  picture  when  that  lens  is  used  over  that  throw. 

Example.  You  have  a  4-inch  lens  and  a  40-foot  throw  and  desire 
to  know  what  size  of  picture  will  be  projected.  At  the  left  of  the  page  find 
the  figure  4  and  place  a  card  across  the  page  so  that  it  will  show  the  row  of 
figures  beginning  with  5.8  and  ending  with  21.0,  thus  showing  a  double  row 
of  pairs  of  which  the  lower  figure  of  each  pair  is  the  larger  of  the  pair.  Now 
find  40  feet  at  the  top  of  one  of  tlie  narrow  columns  and  below  it  is  found 
the  pair  of  figures,  6.8—9.3,  meaning  that  with  that  lens  and  that  throw  the 
picture  will  be  6  feet  9^  inches  in  heiglit  and  9  feet  3\  inches  in  width. 

To  Take  the  Length  of  Throw.  Knowing  the  lens  which  must 
be  used  and  the  size  of  picture  desired,  look  at  the  left  of  the  table 
for  the  lens  length,  place  a  card  across  the  page  and  look  along  the 
card  for  the  size  of  picture,  then  go  up  the  column  to  the  top  and 
there  will  be  found  the  length  of  throw  which  will  give  that  size  pic- 
ture with  that  lens. 

Example.  In  a  parlor,  a  screen  6  feet  square  has  been  provided;  you 
have  only  a  4-inch  Jens.  At  the  left  of  the  page,  find  the  figure  4  and  lay 
a  card  across  tlie  page;  the  first  pair  of  figures  along  the  edge  of  the  card  is 


01 


18  THE  MOTION  PTCTFRE 

4.2-5.8,  which  will  go  on  the  screen,  but  the  next  pair,  5.1-7.0,  will  give  a 
picture  too  large  for  the  screen.  It  is  seen,  therefore,  that  the  operator  must 
not  place  his  projecting  machine  farther  away  than  25  feet  (the  figure  at  top 
of  column  above  the  pair,  4.2—5.8)  or  the  projected  picture  will  be  too  large 
for  the  screen. 

Accurate  Calculations.  ^Mien  sizes  are  needed  very  accurately, 
they  should  be  calculated  according  to  the  rules  given  for  calculating 
data  for  lenses  for  lantern  slides  for  the  optical  lantern,  using  the 
three  equations; 

ST  =  PD  (I) 

F2  =  (^D  -  F)(T  -  F)  (2) 

D  +  T  =  H  (2) 

In  these  equations,  when  used  in  the  calculation  of  data  for  motion 
picture  projection, 

S  equals  the  width  of  the  film  aperture  or  mask  opening  when 
calculating  for  the  width  of  the  projected  picture — make  S  equal 
to  1  inch  or  %  inch  according  to  the  dimension  of  the  aperture — 
and  equals  the  height  of  the  film  aperture  when  calculating  for  the 
height  of  the  projected  picture — make  S  equal  to  f  inch  or  %  inch, 
according  to  the  dimension  of  the  aperture. 

T  equals  the  length  of  throw,  lens  to  screen,  which  may  be 
measured  closely  when  the  length  of  the  lens  is  known  approximately, 
and  when  T  may  be  measured  the  equation  for  S  may  be  written 
in  a  simpler  form  if  desired. 

P  equals  the  picture  dimension  as  projected  on  the  screen,  being 
the  height  when  8  is  the  height  and  being  the  width  when  S  is  the 
width  of  the  film  aperture. 

D  equals  the  distance  from  the  focal  center  of  the  lens  to  the 
picture  film  in  the  film  window;  it  is  not  required  to  be  known  in 
the  course  of  calculations,  but  is  included  in  the  equations  because 
it  influences  the  size  of  the  projected  picture,  sometimes  as  much  as 
1  inch  in  the  width  of  a  picture  12  feet  wide. 

F  equals  the  focal  length  in  inches  of  the  motion-picture  objective 
or  projecting  lens. 

//  equals  the  distance,  screen  to  film. 

Approximate  Calculations.  Use  the  formulas  or  equations  given 
for  lantern  slides.  These  calculations  are  useful  when  the  exact 
length  of  throw  is  not  given  in  the  table. 


92 


MOTION  HEAD  10 

The  throw  equals  the  desired  picture  width  multiplied  by  the 
focal  length  of  the  lens  and  divided  by  the  film  aperture  width,  all 
dimensions  taken  in  inches.    That  is 

T  =  PxF  -r  S 

The  lens  length  equals  the  film  aperture  width  multiplied  by  the 
length  of  throw  and  divided  by  the  desired  picture  width,  all  dimen- 
sions taken  in  inches.     That  is 

F  =  SXT  -rP 

The  picture  width  equals  the  film  aperture  width  multiplied  by 
the  length  of  throw  and  divided  by  the  focal  length  of  the  lens,  all 
dimensions  taken  in  inches.    That  is 

p  ^  SXT  -r  F 

The  picture  height  equals  the  film  aperture  height  multiplied  by 
the  length  of  throw  and  divided  by  the  focal  length  of  the  lens,  all 
dimensions  taken  in  inches.     That  is 

P  =  SXT  -r  F 

Calculations  Compared.  Assume  a  4-inch  lens  and  a  48-foot 
throw.  The  accurate  calculation  gives  a  picture  size  of  11  feet  11 
inches,  while  the  simpler  approximate  calculation  gives  a  picture 
size  of  12  feet,  approximating  the  true  picture  size  within  1  inch. 

Matched  Lenses — Stereo  and  Motion  Head.  By  the  term  matched 
lenses  is  meant  a  pair  of  lenses  selected  to  work  together,  the  one  as 
a  motion-head  lens  and  the  other  as  a  stereo  lens,  and  to  give  two 
pictures  upon  the  screen  which  shall  have  the  desired  relation  in  size. 

Lenses  may  be  matched  for  height,  for  width,  or  for  area.  If 
the  screen  is  square,  the  stereo  lens  may  be  matched  to  project  a 
picture  as  wide  as  the  motion  picture  lens.  If  the  screen  is  the  shape 
of  the  motion  picture,  then  the  stereo  lens  may  not  project  a  picture 
higher  Mian  the  motion-picture  projection.  If  the  screen  is  between 
the  two,  or  if  it  is  ample  in  size  and  the  operator  prefers  a  picture 
of  equal  area,  the  lenses  may  be  so  matched.  The  argument  in  favor 
of  equal  area  is  that  the  shift  from  lantern  slide  to  motion  film  is  less 
objectionable  to  the  operator,  but  when  the  possible  difference  in 
densities  is  considered  this  objection  seems  to  have  little  force. 

To  match  lenses  for  the  samo  width  of  picture  on  the  screen, 
the  stereo  lens  will  be  just  three  times  the  focal  length  of  the  motion 


83 


20 


THE  MOTION  PICTURE 


Fig.  5.  DiaRram  of  Edges  of 
Pictures  on  Screen  with  Lenses 
Matched  to  Give  Equal  Area 


picture  lens,  figuring  1  inch  as  the  width  of  the  window  in  the  film 
gate  and  3  inches  as  the  width  of  the  mask  opening  of  the  lantern 

sHde.  With  the  'Ae-inch  film  wnndow, 
the  stereo  lens  should  have  three  and 
one-fifth  times  the  focal  length  of  the 
motion-head  lens. 

For  equal  height  of  picture  on  the 
screen,  |-inch  high  film  window,  and 
2f-inch  high  lantern  slide  mask  open- 
ing, the  stereo  lens  should  be  three 
and  two-thirds  the  focal  length  of  the 
motion-head  lens;  and  with  a  film 
T\-indow  j^l  inch,  the  stereo  lens  should 
be  four  times  the  focal  length  of  the  motion  lens. 

For  equal  areas,  the  stereo  lens  should  be  three  and  one-third 
times  the  focal  length  of  the  motion-head  lens  for  a  film  window 
f  inch  by  1  inch  or  full  size  of  the  motion  film.  The  stereo  lens  should 
be  about  three  and  three-fifths  the  focal  length  of  the  motion-head 
lens  for  a  film  window  ||  inch  by  ^-|  inch.  The  arrangement  or 
relation  of  the  two  pictures  upon  the  picture  screen  when  projected 
matched  for  area  is  shown  in  Fig.  5. 

Adjustable  Lenses.  These  lenses  are  made  to  change  the  equiva- 
lent focal  length  of  the  lens  by  turning  the  front  rim  of  the  lens.  Fig. 

6.  The  knob  moves  the  whole  lens. 
Such  a  lens,  at  a  40-foot  throw,  will 
project  a  picture  varjang,  say,  from 
8  feet  in  width  to  14  feet  in  width; 
that  is  to  say,  its  focal  length  can  be 
adjusted  from  2h  inches  to  nearly  5 
inches  by  turning  the  front  rim. 
After  turning  the  front  rim  to  change 
the  picture  size,  the  lens  must  be  re- 
adjusted with  the  knurled  knob  to 
focus  properly  on  the  screen.  The 
price  is  as  much  as  two  or  three  ordinary  lenses  of  the  same  quality. 
Any  lens  will  project  its  picture  slightly  smaller  by  imscrewing  front 
and  back  lens  cells  a  few  turns  of  the  screws.  This  is  not  to  be  rec- 
ommended for  indiscriminate  practice. 


Fig.  6.     A  Lens  Having  Adjustable 
Focal  Length,  for  Motion  Head 


94 


MOTION  HEAD  21 

THE  SHUTTER 

In  projection  by  persistence  of  vision,  the  secret  of  successful 
work  is  to  make  the  change  of  picture  on  the  screen  without  per- 
mitting the  spectator  to  see  or  to  appreciate  the  change  in  any  way 
other  than  by  the  shift  of  the  moving  objects  in  the  image  portrayed. 
Theoretically,  it  is  possible  to  shift  the  picture  by  a  jerk  so  quick 
that  the  transfer  from  the  old  to  the  new  picture  is  made 
without  leaving  upon  the  eye  of  the  spectator  an  impression  of  mo- 
tion of  the  fixed  objects  because  the  motion  was  so  brief. 

That  this  is  possible  is  proven  by  the  successful  operation  of 
many  shutterless  toy  projectors,  projecting  film  of  standard  dimen- 
sions by  means  of  an  oil  lamp  upon  a  small  screen,  such  as  3X  4  feet. 
The  picture  is  steady  and  flickerless.  The  result  is  dependent  upon 
the  weak  illumination  of  the  oil  lamp.  \Mien  a  miniature  incandes- 
cent lamp  is  placed  in  such  a  toy  machine  and  caused  to  glow  brightly 
by  a  sufficient  battery,  thereby  increasing  the  intensity  of  illumina- 
tion upon  the  screen,  the  shifting  becomes  apparent  at  once,  mani- 
festing itself  by  "rain"  or  "light  rain,"  sometimes  called  "halo." 
This  is  a  streaking  of  the  picture  vertically,  caused  by  the  rapid 
passing  of  the  light  spots  of  the  pictures  while  moving. 

To  avoid  "light  rain,"  the  motion  head  is  provided  with  a  shutter 
for  cutting  off  the  light  from  the  picture  screen  while  the  film  is  in 
motion  during  the  shift.  This  obscures  the  "light  rain"  and  gives 
again  a  satisfactory  projection,  until  the  intensity  of  illumination 
is  increased  further,  when  the  picture  change  begins  to  become 
apparent  again,  this  time  by  a  flickering  of  the  illumination  of  the 
screen  everv  time  the  shutter  cuts  off  the  lig-ht  for  the  change. 

To  make  the  flicker  less  noticeable,  effort  is  made  to  reduce  the 
time  of  the  dark  inteiTal  until  it  falls  within  the  limits  of  persistence 
of  vision.  With  the  widely  used  "Geneva"  movement  for  the  inter- 
mittent mechanism,  it  is  feasible  to  have  the  film  stand  still  four- 
fifths  of  the  total  picture  time  of  one-fourteenth  of  a  second,  making 
the  change  of  pictures  in  the  remainder  of  one-fifth  of  one-fourteenth 
of  a  second,  or  in  one-seventieth  of  a  second;  but  the  shutter  begins 
to  cut  off  the  light  before  the  film  begins  to  move  and  then  does  not 
restore  the  full  light  until  after  the  film  has  come  to  rest,  thus  lengthen- 
ing the  interval  of  reduced  light.     Furthermore,  the  more  intense 


95 


22  THE  MOTION  PICTURE 

the  screen  illumination,  the  more  noticeable  is  the  flicker  for  the  same 
shutter  setting  and  the  same  machine  speed,  indicating  that  the  bril- 
liancy of  the  picture  screen  has  some  effect  upon  the  time  during 
which  the  vision  will  persist. 

In  the  same  audience,  one  person  will  see  flickering  pictures 
where  another  will  not,  because  of  the  difference  in  the  eyes.  Suc- 
cessive scenes  in  the  same  reel  of  film  will  show  flicker  or  not  to  the 
same  spectator  because  of  the  difference  in  the  opacity  of  the  film 
image.  A  scene  with  a  bright  white  sky  will  flicker  unendurably  to 
nearly  all  eves  while  the  interior  view  following  it  will  run  smoothly 
because  of  the  smaller  amount  of  light  on  the  screen. 

The  multiple  shutter  is  an  invention  for  reducing  flicker.  It  is 
used  on  many  prominent  machines.  The  form  may  be  disk,  barrel, 
or  cone.  The  principle  is  that  of  shutting  off  the  light  twice,  or  three 
times  for  each  picture  projected,  so  that  the  rapidity  of  flicker  is 
increased  until  the  flicker  becomes  so  fast  that  the  eye  cannot  appre- 
ciate the  separate  flickerings  and  blends  them  all  together  into  a  con- 
tinuous steady  illumination  by  reason  of  the  persistence  of  vision. 
In  the  operation  of  this  shutter,  the  light  is  cut  off  from  the  screen 
forty-two  times  per  second  and  the  picture  is  changed  to  the  next 
step  of  the  film  only  fourteen  times  per  second,  or  every  third  time 
the  light  is  cut  oft'. 

^Yith  a  shutter  having  but  one  blade,  cutting  the  light  from 
the  screen  only  when  the  picture  is  being  changed,  four-fifths  of 
the  light  of  the  lantern  is  projected  to  the  screen.  With  the  multiple 
shutter  which  shuts  off  one-sixth,  then  leaves  the  light  on  one-sixth, 
then  shuts  off  one-sixth,  and  so  on,  the  light  given  to  the  screen  is 
three-sixths  on  and  three-sixths  off  for  every  picture,  giving  but  one- 
half  of  the  lantern's  light  to  the  screen.  Thus  the  multiple  shutter 
reduces  the  maximum  illumination  and  thereby  reduces  the  flicker, 
even  as  flicker  would  be  reduced  if  the  operator  would  reduce  the 
current  through  his  arc  and  give  a  less  bright  projection  in  that  way. 
The  multiple  shutter  much  improves  the  projection  in  the  detail  of 
flicker. 

Adjust  the  shutter  accurately,  whether  single  or  multiple  wing 
and  keep  the  machine  running  fast  enough  to  keep  the  flicker  sul> 
dued.  In  scenes  which  have  a  particularly  bright  screen  illumina- 
tion, the  light  may  be  reduced  by  a  t inter,  which  is  a  sheet  of  colored 


96 


MOTION  HEAD  23 

glass  or  a  plain  colored  lantern  slide  or  the  equivalent,  which  may 
be  held  either  between  the  lens  and  the  screen  or  between  the  con- 
densers and  the  film  window 

Types  of  Shutters.  There  are  two  principal  types  of  shutters, 
the  barrel  shutter  and  the  disk  shutter,  the  latter  amplified  ^o  the 
double-disk  shutter  to  secure  the  advantages  of  the  barrel  type. 

Barrel  Shutter.     The  barrel  shutter  is  shown  in  Fig.  7.    This 
shutter  is  like  a  barrel  with  two  windows  cut  in  it.     ^Yhen  it  is  ar- 
ranged to  shut   off   the   light  as  a  single  shutter, 
cutting  the  screen  dark  once  for  each  picture  shift, 
then  it  revolves  at  one-half  the  speed  of  the  inter- 
mittent mechanism,  or  one  revolution  of  the  shutter 
for  two   pictures.     The  light  is  admitted   to   the 
screen  when  the  two  windows   of   the   barrel  are 
opposite  each  other  horizontally.     The  advantage 
which  this  shutter  has  over  the  disk  is  the  speed 
with  which  it  cuts  the  light  from  the   screen    and 
restores  it  after  the  shift.    The  blade  near  the  lens 
begins  to  cut  the  upper  rays  and  the  blade  near    ^%\^.^q  J^ihutter^ 
the  film  window   begins    to    cut    the   lower   rays, 
and   when   the  shutter  is  half  over  the  beam  of  light,  the  light  has 
been  shut  off,  because  the  shutter  has  worked  upon  both  halves  at 
the  same  time.    In  like  manner,  when  the  shutter  begins  to  admit 
the  light  to  the  screen  again,  it  begins  at  the  middle  and  as  the  blades 
separate  the  light  spreads  upon  the  lens  rapidly  toward  the  upper 
and  lower  edges,  restoring  the  full  illumination  very  quickly.     This 
shutter  usually  is  placed  between  the  lens  and  the  film  window,  as 
shown  in  the  diagram.     For  the  multiple-shutter  effect,  the  barrel 
shutter  revolves  once  for  each  picture,  cutting  the  light  off  twice. 
The  blades  then  are  wider,  the  windows  smaller. 

Disk  Shutter.  The  disk  shutter  is  a  plain  disk  with  a  window  in 
it,  or  a  hub  with  a  single  wing  attached,  revolving  edgewise  as  shown 
in  Fig.  S.  It  is  placed  in  any  one  of  three  places — between  the  lens 
and  the  film  window;  between  the  condensers  and  the  film  window; 
or  before  the  lens.  It  is  desirable  that  the  light  be  cut  off  as  quick 
as  possible  when  the  shutter  begins  to  cut  it  off,  and  that  it  be  re- 
stored just  as  quickly  when  the  shutter  begins  to  restore  it.  This  ad- 
vantage was  enjoyed  by  the  barrel  shutter  over  the  disk  shutter  so 


97 


24 


THE  MOTION  PICTURE 


long  as  the  disk  shutter  remained  of  small  radius;  the  small  radius  was 
enforced  when  the  shutter  was  placed  between  the  lens  and  the  film 
window  because  it  must  be  contained  then  within  the  body  of  the 
projecting  machine;  when  placed  between  the  film  window  and  the 
condensers,  its  size  was  restricted  also,  because  on  the  one  hand  it 
conflicted  with  the  crank,  and  on  the  other  hand  with  the  stereo- 
lens  beam  of  light. 

Before  the  Lens  Shutter.      The  before-the-lens  shutter  solved  the 
problem  of  the  quick  cut  off  for  the  light  with  the  simple  disk  shutter. 


Fig.  8.     The  Disk  Type  of  Shutter,  with  Two  and  Three  Wings 

The  shutter  was  placed  before  the  lens  and  was  made  of  large  radius. 
The  speed  of  the  shutter  near  the  edge  of  a  lo-inch  disk  is  seven  times 
that  of  the  shutter  within  the  motion  head  which  had  an  axis  only 
2  inches  from  the  optical  axis  of  the  beam  of  light,  and  when  the 
edge  of  the  wing  comes  to  the  beam  of  light  streaming  from  the 
lens,  the  beam  is  cut  very  quickly.  True,  the  beam  of  light  at  this 
point  is  larger  than  it  is  between  the  lens  and  the  film  window,  but 
the  speed  of  the  cutting  shutter  wing  is  still  greater  in  proportion. 
With  the  disk  shutter  for  the  multiple  shutter  effect,  it  may 
carry  three  wings,  each  one-sixth  of  the  circumference  of  the  shutter, 


98 


MOTION  HEAD  25 

or  the  shutter  of  two  wings  may  be  driven  at  one  and  one-half  times 
the  rate  of  the  picture  shift  to  reduce  the  flicker,  Fig.  8. 

Any  shutter  may  give  the  multiple  shutter  effect  to  reduce  the 
flicker  by  doubling  the  speed,  where  the  mechanical  details  of  the 
motion  head  permit  it. 

Multiple-Disk  Shutter.  This  is  a  shutter  consisting  of  two  disks 
revolving  in  opposite  directions,  so  that  they  begin  at  the  same  time 
to  cut  off  the  light  from  both  edges  of  the  beam,  just  as  the  barrel 
shutter  does.  This  makes  the  cut-off  still  more  quickly  than  the 
single-disk  shutter  and  serves  still  further  to  reduce  the  flicker. 
In  multiple-disk  shutters  the  disks  are  not  always  mounted  upon 
the  same  shaft  or  upon  the  same  axis,  one  disk  sometimes  working 
from  one  side  of  the  beam  of  light  and  the  other  disk  from  the  other 
side. 

Cone  Shutter.  ^Vith  its  driving  shaft  set  at  an  angle  of  45°  to 
the  beam  of  light,  the  cone  shutter  revolves  its  two  wings — one  in 
the  beam  of  light  and  the  other  at  the  side-  parallel  with  the  beam. 
The  cone  shutter  is  a  shape  adapted  to  save  space  in  the  motion 
head,  and  give  the  advantages  of  the  disk  without  taking  the  room. 

Setting  the  Shutter.  Here  is  a  short  rule  which  applies  to  every 
type  of  shutter  and  to  every  type  of  intermittent  mechanism: 

Place  a  piece  of  film  in  the  motion  head,  threaded  through  the 
film  gate  and  intermittent  feed  of  whatever  nature,  and  frame  the 
picture  true  in  the  film  aperture,  splitting  the  margin  of  trim  if  you 
are  running  a  %  aperture  on  a  |"  picture.  Then  advance  the  in- 
termittent mechanism  until  the  film  is  being  shifted  and  is  exactly 
in  the  middle  of  the  shift.  At  this  point,  the  line  of  division  of  the 
film  between  the  two  pictures  u'ill  be  exactly  across  the  middle  of  the 
film  windoic.  Noio  set  the  shutter  so  that  it  is  dead  center  over  the 
lens,  or  dead  center  on  the  optical  axis. 

If  you  have  a  multiple  shutter  and  one  of  the  leaves  of  the  shutter 
is  broader  than  the  others,  or  if  one  is  opaque  and  the  others  trans- 
lucent, then  the  broad  leaf  or  the  opaque  leaf  is  the  one  to  set  over 
the  lens  when  the  film  is  half  shifted.  ^^ 

Another  rule,  which  applies  only  to  the  Geneva  shift  and  the 
disk  shutter,  is: 

When  the  pin  is  half  in  the  slot,  the  shutter  should  be  half  over 
the  lens. 


99 


26  THE  MOTION  PICTURE 

Fire  Shutter.  The  fire  shutter,  or  safety  shutter,  shown  at  A"^ 
in  Fig.  4,  is  a  requirement  of  most  city  ordinances.  It  is  a  shutter 
for  cutting  the  rays  of  the  arc  lamp  from  the  film  window  when  the 
motion  head  is  not  running.  It  is  called  automatic  when  it  is  so 
arranged  that  it  will  fall  into  place  and  cut  oft'  the  light  when  the 
film  stops,  without  requiring  the  attention  of  the  operator  to  close 
it.  Sometimes  its  mechanism  is  such  that  when  the  handle  is  turned 
it  is  lifted  from  the  film  window  automatically,  and  sometimes  it  is 
such  that  a  definite  speed  must  be  attained  before  it  will  be  lifted 
from  the  film  window. 

This  fire  shutter  is  a  detail  wliich  varies  greatly  with  different 
makes  of  motion  heads.  Its  general  purpose  is  the  same  in  all — to 
protect  the  film  from  the  intense  heat  of  the  arc  in  case  the  film  should 
stop  in  the  film  window,  for  the  arc  would  cause  the  film  to  burst  into 
flame  in  a  few  seconds. 

FILM  GATE 

The  mechanism  of  the  film  gate  is  so  simple  that  unless  its 
fiuictions  or  the  duties  dependent  upon  it  are  understood  the  pro- 
jection operator  is  liable  to  neglect  it.  It  is  one  of  the  ver}'  important 
parts  to  be  kept  in  exact  condition  of  adjustment  and  to  be  corrected 
when  the  slightest  wear  shows,  for  one  of  its  duties  is  the  keeping 
of  the  focus  constant  upon  the  screen.  It  is  of  little  use  to  adjust 
the  objective  lens  to  focus  the  film  upon  the  screen  in  one  minute 
when  the  film  gate  will  change  the  position  of  the  film  and  throw  it 
out  of  focus  the  next. 

Functions.  The  functions  of  the  film  gate  are:  First,  to  guide 
the  film  so  as  to  prevent  any  side  wise  motion  as  it  passes  in  front  of 
the  film  window  in  the  aperture  plate. 

Second,  to  flatten  the  film  at  the  film  window  and  hold  it  flat 
so  that  all  of  the  surface  of  the  film  picture  may  be  thrown  into  focus 
upon  the  picture  screen  by  a  flat-field  lens,  and  to  hold  it  in  the  same 
plane  all  the  time  so  that  the  focus  when  once  established  by  the  ad- 
justment of  the  objective  lens  will  be  maintained  to  the  end  of  the 
reel  and  through  successive  reels. 

Third,  to  prevent  vertical  jiggling  of  the  images  of  the  series  in 
their  comparative  locations  in  the  film  window,  by  putting  upon  the 
film  a  tension  or  restraint  to  keep  it  from  following  by  its  momentum 
after  the  intermittent  mechanism  has  stopped  pulling. 


100 


MOTION  HEAD  27 

Construction.  The  main  plate  has  t^o  side  guides  or  rails  and 
a  film  aperture  or  film  window.  The  two  side  rails  are  separated 
sufl^ciently  to  permit  the  film  to  pass  between  but  not  to  take  any 
diagonal  position.  When  threading  up  the  machine,  the  film  is 
placed  in  the  groove  formed  by  the  face  of  the  film  gate  and  the  two 
shoulders  or  rails  forming  the  side  guides  for  the  film;  and  the  ten- 
sion plate  or  tension  springs  are  brought  to  bear  upon  the  edges  of 
the  film. 

In  Fig.  4,  the  body  of  the  film  gate  is  represented  at  G  and  the 
tension  plate  at  //.    The  springs  are  not  shown. 

Adjustment  of  Tension  Springs.  Where  the  tension  springs 
do  not  make  direct  pressure  upon  the  edges  of  the  film,  the  tension 
plate  is  pressed  by  tension  springs  which  are  adjustable.  If  the 
tension  of  these  springs  is  too  tight,  they  will  drag  the  film  at  such 
strain  that  a  weak  place  or  splice  will  separate  under  the  pull  of  the 
intermittent  feed ;  if  the  tension  of  the  springs  is  too  loose,  the  picture 
will  "follow"  and  the  projected  image  upon  the  screen  will  jiggle 
vertically.  As  the  tight  spring  does  not  manifest  itself  imless  it  be 
by  tearing  the  film  or  causing  the  handle  to  turn  hard,  it  is  less  easily 
detected  upon  inspection  than  the  loose  spring,  W'hich  permits  the 
picture  to  jiggle.  The  adjustment  of  the  tension  springs  may  be 
attained,  therefore,  first  by  setting  all  of  them  to  the  same  tension, 
then  by  loosening  them  equally  until  the  picture  begins  to  show  upon 
the  screen  that  the  tension  springs  are  too  loose;  then  by  tightening 
them  until  the  picture  is  steady  again.  Thus  they  will  be  tight  enough, 
without  excess  pressure. 

Care.  The  film  gate  and  the  tension  plate  both  wear  where 
the  film  rubs  between  them;  where  the  springs  press  directly  upon 
the  film,  the  springs  themselves  wear.  Any  wear  which  can  be  de- 
tected will  probably  be  enough  to  throw  the  picture  out  of  focus  upon 
the  screen  from  time  to  time,  particularly  a  film  which  is  slightly  warped. 

The  only  remedy  for  a  worn  film  gate,  which  permits  the  focus 
of  the  picture  to  vary  from  time  to  time  as  the  reel  is  turned  through, 
and  the  lens  remains  stationary,  is  to  buy  new  parts — gate  body 
(with  some  makes  of  machines  it  is  the  "aperture  plate"),  or  new  ten- 
sion plate,  or  springs,  or  all  of  them. 

Wear  can  be  reduced  and  the  machine  will  pull  easier  on  the 
handle  if  the  film  gate  and  tension  plate  surfaces,  which  are  rubbed 


101 


28  THE  MOTION  PICTURE 

by  the  film,  are  kept  free  from  any  gelatine  which  may  come  off  of 
the  film.  Clean  them  every  time  by  wiping  before  threading  up  the 
new  reel,  and  by  wiping  with  an  oily  rag  every  time  a  new  reel  is  put 
in — the  rag  should  be  oily  but  so  dry  that  it  is  not  running  oil  when 
squeezed  in  the  hand.    Never  oil  them  with  an  oil  can. 

FILM  SHIFT  OR  INTERMITTENT  MOVEMENT 

There  are  many  variations  in  devices  for  stepping  the  strip  of 
film  forward  the  three-quarters  of  an  inch  from  one  picture  to  the 
next  of  the  series.  The  requirement  of  such  a  device  is  very  severe, 
for  the  step  must  be  made  with  great  speed  and  with  great  accuracy, 
and  furthermore  the  film  must  be  permitted  to  remain  perfectly 
motionless  during  the  interval  between  steps.  A  class  of  projectors, 
which  does  not  use  the  intermittent  movement,  will  be  considered 
in  connection  with  continuous  projection  devices. 

The  different  mechanisms  for  making  the  shift  of  the  film  upon 
the  step-by-step  principle  are:  the  sprocket;  the  pin;  the  claw;  the 
beater;  and  the  intermittent  grip. 

Intermittent  Sprocket.  The  intermittent  sprocket  is  a  wheel 
with  two  circles  of  pointed  teeth  spaced  a  trifle  more  than  1  inch 
apart  upon  the  surface  of  a  drum  about  1  inch  in  diameter,  or  spaced 
upon  two  hubs  or  bosses  to  hold  them  at  that  distance,  the  metal 
being  cut  away  to  render  the  wheel  light  of  weight  and  easily  started 
and  stopped.  The  sprocket  teeth  are  spaced  so  as  to  engage  the 
perforations  of  the  edges  of  the  film  strip,  and  the  film  is  advanced 
step  by  step  by  turning  the  sprocket  wheel  intermittently,  usually  one- 
quarter  of  a  revolution  for  each  step  of  the  film. 

For  turning  the  sprocket  wheel  in  its  intermittent  motion,  a 
large  variety  of  devices  have  been  employed,  and  a  new  one  is  brought 
out  occasionally.  The  only  test  for  a  new  intermittent  movement 
is  the  test  of  time.  Nearly  all  intermittents  ever  used  have  given 
place  to  the  Geneva,  which  was  among  the  earliest  of  them  all. 

Geneva  or  Pin=and=Star.  The  Geneva  movement  comprises 
a  star  wheel  shaped  like  a  modified  Maltese  cross  and  attached  to 
the  sprocket  shaft,  and  a  pin  wheel  which  revolves  steadily.  Every 
time  the  pin  comes  around  it  catches  a  wing  of  the  Maltese  cross 
and  throws  the  cross  around  one-quarter  of  a  turn,  leaving  it  there 
until  the  pin  comes  around  again. 


102 


MOTION  HEAD  29 

A  Geneva  movement — it  is  called  Geneva  because  it  was  used 
first  in  Geneva,  Switzerland,  in  watches,  with  one  of  the  wings  of 
the  cross  convex  instead  of  concave  so  that  the  main  spring  of  the 
watch  could  not  be  wound  too  far — is  shown  in  perspective  view  in 
Fig.  9.  At  the  left  is  the  star  wheel,  with  four  slots  and  four  wings 
each  having  a  concave  outer  face,  as  indicated  at  A.  The  pin  wheel 
is  seen  at  the  right,  and  consists  of  a  flat  disk  or  face  plate  carrying 
a  pin  B  and  the  cam  band  C.  The  cam  band  is  cut  away  on  both 
sides  of  the  pin  and  the  pin  is  set  outside  of  the  cam  band  circle,  or 
a  litde  farther  from  the  center  hole  of  the  disk.  When  the  pin  wheel 
revolves,  toward  the  left,  say — although  it  depends  upon  the  particular 
projecting  machine  or  camera 
inspected,  for  the  Geneva  move- 
ment may  be  on  either  end  of 
the  intermittent  sprocket  shaft — 
the  pin  moves  toward  the  left 
and  when  the  pin  comes  to  the 
star  wheel  it  enters  the  open  end 
of  the  slot  next  to  the  wing 
which    has    been    against    the 

moving  cam  band;  but  the  cam       r^-     „     ^  t  .      •..    .  »c 

o  '  Fig.  9.     Geneva  Intermittent  Movement 

band    now    has    released    that 

wing  and  the  pin  in  moving  into  the  slot  presses  against  the  side 
of  the  wing  and  turns  the  star  wheel  as  two  meshing  gear  wheels 
would  turn  each  other,  except  that  the  pin  starts  the  star  wheel 
slowly,  swings  it  rapidly  during  the  middle  portion  of  its  movement, 
and  again  slows  it  up  to  a  standstill  before  leaving  the  slot.  The 
pin  enters  the  slot,  which  is  shown  diagonally  upward  to  the  right, 
and  having  turned  the  star  one-quarter  of  a  revolution  the  pin  leaves 
the  same  slot  diagonally  downward  to  the  right,  the  cam  bend  hav- 
ing come  around  following  the  pin  to  engage  the  concave  surface  of 
the  next  wing  before  the  pin  has  left  the  slot  entirely. 

The  advantages  of  the  Geneva  movement  are:  (1)  It  starts 
the  film  with  a  slow  movement,  increasing  the  speed  to  a  maximum, 
then  decreasing  the  speed  until  the  film  comes  slowly  to  rest.  (2)  It 
holds  the  film  or  sprocket  firmly  locked  during  the  interval  of  rest 
between  shifts.  (3)  It  is  very  easy  in  the  wear  of  the  sprocket  holes 
of  the  film  because  of  the  lack  of  jerk  in  starting  the  film.    (4)    It  is 


103 


30  THE  INIOTION  PICTURE 

very  gentle  with  weak  or  injured  places  in  the  film  which  might  yield 
and  permit  the  film  to  be  torn  apart  if  suddenly  jerked.  (5)  It  is 
capable  of  construction  in  such  proportions  that  any  desired  ratio 
of  time  of  movement  as  compared  with  time  of  rest  may  be  attained. 
To  change  the  ratio  of  movement  and  rest  of  the  sprocket  wheel 
and  film,  the  relative  diameters  of  the  two  wheels  are  changed.  With 
a  larger  diameter  of  pin  wheel,  the  breadth  of  the  wing  surface  A 
which  rests  upon  the  cam  band  will  be  a  smaller  part  of  the  whole 
circumference,  hence  the  pin  B  must  affect  the  shift  of  the  star  w^heel, 
sprocket,  and  film  during  a  smaller  proportion  of  its  total  travel, 
or  of  one  revolution.  The  ratio  between  the  diameters  of  the  two 
wheels  determines  the  ratio  of  movement  to  rest,  the  ratio  of  rotation 
beino-  four  of  the  pin  wheel  to  one  of  the  star  wheel  in  any  case,  re- 
gardless of  the  relative  diameters  of  the  wheels. 

Double  Star.  The  double  star  movement  consists  of  tw^o  Geneva 
movements  working  in  the  same  machine,  one  above  the  film  gate 
and  one  below  the  film  gate.  The  theory  is  that  they  assist  in  keep- 
ing the  film  flat  by  keeping  it  taut  between  them,  also  that  they 
reduce  the  strain  upon  the  film  by  giving  the  lower  sprocket  less 
pulling  to  do.  This  mechanism  sometimes  operates  both  star  wheels 
from  one  pin  wheel,  in  which  case  there  are  two  pins  in  the  pin  wheel, 
the  two  pins  operating  the  two  stars  simultaneously. 

Double  Pin.  The  double  pin  movement  is 
merely  a  modification  of  the  Geneva  movement 
by  w^hich  the  star  wheel  takes  a  step  every  half 
revolution  of  the  pin  w^heel,  instead  of  every 
full  revolution.  It  is  shown  in  diagram  in  Fig.  10. 
The  only  advantage  urged  is  that  the  speed  of 
the  pin  wheel  is  reduced  to  half  that  required 
were  the  single  pin  used.  The  simple  Geneva 
is  the  more  widely  adopted. 

Pitman.    The  pitman  movement  is  illustrated 
_.     ,„     T^    ,,   TT       in  Fig.  11.    The  intermittent  sprocket  is  carried 

Fig.   10.      Double-Pm  ^  r 

^^°®Moveraent"^"        ^y    *^^    ^^^^^^    Carrying    the    ratchet  wheel   R. 

Since  the  ratchet  in   the  figure  is  shown  with 

seven  teeth,  the  sprocket  attached  would  require  twenty-eight  teeth  to 

feed  the  standard  four-hole  film.    The  wheel  C  is  the  constant  drive, 

and  the  face  of  the  wheel  C  carries  a  wrist  pin  driving  a  pitman  bar, 


104 


MOTION  HEAD 


31 


Pitman  Intermittent 
Movement 


which  in  turn  drives  the  pawl  engaging  into  the  ratchet  R.  The  pawl 
upon  the  top  of  the  ratchet  R  prevents  return  of  the  ratchet  during  the 
return  stroke  of  the  pitman  and  driving 
pawl.  As  the  wheel  C  may  be  designed  to 
drive  the  pawl  over  a  greater  stroke  than 
the  distance  between  two  ratchet  teeth, 
this  device  also  may  have  a  designed  ratio 
of  time  of  movement  to  time  of  rest;  unless 
the  movement  is  approximately  half-and- 
half  the  start  of  the  film  will  be  a  sudden 
jerk. 

Ratchet.  The  ratchet  movement  is  ^^s-  n. 
illustrated  in  Fig.  12.  The  sprocket  wheel 
is  attached  to  the  same  shaft  as  the  ratchet  wheel  M  and  the 
ratchet-shape  wheel  iV  is  driven  steadily.  The  wheels  move  in 
the  same  direction,  as  is  indicated  by  the  arrows,  and  they  are 
connected  by  a  volute  spring.  With  six  teeth  in  the  ratchets,  the 
sprocket  would  have  twenty-four  teeth  for  a  standard  film.  The 
pawl  N  swings  upon  a  fixed  pivot  and  engages  both  of  the  toothed 
wheels.  Its  function  is  to  hold  the  intermittent  wheel  ^f  at  rest 
until  the  pawl  is  lifted  by  the 
steady  drive  iV,  at  which  time 
the  pawl  slips  the  tooth  of  the 
intermittent,  but  in  turn  slips  a 
tooth  of  the  steady  drive  so  soon 
thereafter  that  it  drops  toward 
the  intermittent  wheel  to  engage 
the  next  tooth  of  that  wheel  and 
to  hold  it  at  rest  until  the  next 
release,  as  compelled  by  the 
steady  drive  N.  The  film  is 
started  by  this  mechanism  gently 
by  the  power  of  the  spring  con- 
necting the  two  wheels  M  and 
N ,  but  it  is  brought  to  rest  with  a 
jerk  by  the  engagement  of  the  intermittent  wheel  M  with  the  pawl  P. 

Drunken=Screw.      The    drunken-screw    intermittent    movement 
involves  a  mechanism  which  is  substantially  a  worm  and  wormwheel, 


Fig.  12.     Ratchet  Intermittent  Movement 


105 


32 


THE  MOTION  PICTURE 


but  the  worm,  instead  of  being  inclined  through  its  full  length,  is 
straight  for  the  greater  part  of  the  circumference  and  then  has  a 


Fig.   13.     Dnmken-Screw  Intermittent  Movement 

sharp  angle.  The  wormwheel,  therefore,  stands  at  rest  during  the 
passing  of  the  straight  portion  of  the  worm  thread,  and  moves  rapidly 
during  the  passage  of  the  inclined  portion  of  the  thread.  The  worm- 
wheel,  which  is  shown  at  K  in  Fig.  13,  is  attached  to  the  intermittent 
shaft,  and  the  drunken  screw  or  worm  G  of  that  figure  is  steadily 
driven. 

Snail.  The  snail  intermittent  movement  comprises  two  wheels 
normally  out  of  engagement,  one  of  which  engages  a  projection  of 
the  other  with  an  incUned  edge  which  propels  the  companion  wheel 
through  a  required  angle.  This  movement  is  shown  in  Fig.  14.  The 
intermittent  wheel  P  is  provided  with  a  number  of  pins,  and  the 
snail  S  engages  a  pin  at  every  re- 
volution and  forces  the  intermittent 
wheel  P  through  the  desired  angle. 


Fig.  14.     Snail  Intermittent 
Movement 


Fig.  15. 


Spring-Latch  Intermittent 
Movement 


Spring  Latch.  The  spring  latch  intermittent  movement  has 
as  its  distinctive  feature  the  holding  and  centering  of  the  sprocket 
for  each  film  picture  by  means  of  a  bent  spring  which  engages  either 
one  tooth,  by  a  notch  in  the  face  of  the  spring,  or  two  teeth  of  the 
wheel,  by  dropping  between  them  with  two  inclined  faces.     When 


II 


106 


Q    =" 
>  •=  i 

H    :?~ 
«    o 

<   BP 
to  i:ti 

w  go 


MOTION  HEAD 


33 


such  a  wheel  is  pushed  over  the  apex  of  the  spring  it  is  propelled  by 
the  spring  to  its  next  position  of  rest  and  held  there  until  again  pro- 
pelled by  the  steady  drive.  Such  an  intermittent  movement  is  shown 
in  Fig,  15.  The  smaller  wheel  is  the  film  sprocket  wheel,  or  fixed 
to  the  film  sprocket  shaft,  while  the  larger  wheel  propels  it  inter- 
mittently, making  a  step  every  time  a  tooth  of  the  large  wheel  en- 
gages a  tooth  of  the 'Small  wheel. 

Single=SprGcket.      The    single-sprocket   intermittent    movement 
is  shown  in  Fig.  16,  which  really  is  a  revolving  claw  movement.    The 


Fig.   16.     Single  Sprocket 
Intermittent  Movement 


Fig.  17.      Modified  Drunker-Screw 

Intermittent  Movement,  End  and 

Top  Views 


sprocket  wheel  moves  with  steady  rotation  and  has  two  pairs  of  teeth. 
As  the  first  of  these  pairs  of  teeth  swing  against  the  film,  they  en- 
gage the  holes  in  the  edge  of  the  film  and  drag  it  down,  leaving  the 
film  unengaged  until  the  other  pair  of  teeth  come  into  engagement 
for  the  next  shift. 

iyiodified  Drunken=Screw.  A  modified  drunken-screw  inter- 
mittent movement  is  shown  in  Fig.  17.  The  intermittent  wheel 
23  tends  to  move  by  friction  clutch  from  the  main  drive,  in  the  direc- 
tion of  the  arrow.  It  is  prevented  from  movement,  however,  by  the 
engagement  of  its  teeth  24  with  the  face  of  the  steady  drive  wheel 
25,  which  has  the  upwardly  turned  wings  29.     The  steady  drive 


107 


34 


THE  :\I()TIOX  PICTT'RE 


shaft  is  20,  the  intermittent  shaft  is  G.  The  spring  30  holds  the 
wheel  .13  against  the  face  of  the  wheel  25  and  prevents  backlash, 
locking  the  film  steady  during  the  intervals  of  rest.  When  the  next 
tooth  29  of  the  wheel  25  comes  to  the  tooth  of  the  wheel  23,  the  wheel 
23  is  started  with  a  blow  and  travels  under  its  friction  clutch  until 
the  next  tooth  engages  the  face  of  the  wheel  25.     Fig.  17  shows  a 

view  of  the  face  of  the  intermittent  wheel 
23  and  the  edge  of  the  steady  drive  wheel 
25  in  the  upper  drawing,  and  the  edge 
of  the  intermittent  wheel  23  and  the  face 
of  the  steady  drive  wheel  25  in  the  lower 
drawing.  The  arrows  show  the  direction 
of  rotation. 

Eccentric  Sprocket.  If  the  lower 
sprocket-roller  of  a  machine  revolves 
continuously  on  a  fixed  axis,  it  will,  of 
course,  continue  to  draw  down  him.  If, 
however,  it  is  mounted  so  that  while  it 
revolves  its  axis  also  rotates  eccentrically  about  a  radius  equal  to 
the  radius  of  the  sprocket,  the  film  will  be  moved  intermittently,  the 
sprocket  simply  rolling  up  along  the  film  for  part  of  a  revolution 
without  moving  it.  Fig.  18  shows  its  arrangement  as  it  is  used  in 
the  Prestwich  camera.     The  sprocket  is  driven  by  a  train  of  gears. 


Fig.    18.      Eccentric   Sprocket  or 

Epicycloidal  Intermittent 

Movement 


Fig.    19.     Pin-Cross  Intermittent  Mechanism 

Pin=Cross.      The   pin-cro.ss    intermittent   mechanism   shown    in 
Fig.  19  has  been  offered  lately.     Its  construction  seems  to  indicate 


108 


MOTION  HEAD 


35 


strength;  the  design  of  the  cam  band  indicates  that  the  shift  is  made 
in  a  \  eiy  small  proportion  of  the  total  time  of  revoliition.  It  is,  there- 
fore, a  movement  bearing  promise,  to  be  proven  bv  use.  The  move- 
ment is  so  new  that  it  still  lacks  an  accepted  name,  but  the  name 
pin-cross  seems  to  be  descriptive.  In  this  movement,  the  member 
shown  separated  at  the  right,  consisting  of  a  cross  of  four  arms,  each 
of  which  bears  a  pin,  is  the  member  attached  to  the  intermittent 
sprocket  shaft.  Thus  attached,  it  meshes  into  the  cam  wheel  at  the 
left,  as  showm  in  dotted  lines.  When  the  broken  or  active  part  of 
the  cam  band  reaches  the  pin-cross,  the  slight  projection  upon  the 
outer  edffe  of  the  small  cam  between  the  ends  of  the  band  throws 
the  leading  outside  pin  outward,  drawing  the  leading  inside  pin  into 
the  slot  before  the  end  of  the  cam  band, 
the  following  outside  pin  also  taking  the 
cross  path  after  the  end  of  the  cam  band, 
the  following  inside  pin  becoming  the 
leading  inside  pin  and  the  leading  out- 
side pin  becoming  the  following  outside 
pin.  Thus,  the  pin-cross  is  turned  one- 
quarter  of  a  revolution,  to  shift  the  film, 
and  is  held  rigid  by  engagement  with 
the  cam  band  at  four  points,  by  the  four 
pins,  until  the  cam  wheel  has  completed 
another  revolution  and  has  come  to  the 
point  for  initiating  another  shift.  Silence 
is  one  of  the  claims  for  this  new  move- 
ment. It  is  used  on  the  Power's  Cameragraph  No.  G,  which  is  ad- 
vertised to  give  the  complete  film  shift  in  one-ninety-sixth  of  a 
second,  giving  the  complete  shift  of  the  film  in  one-sixth  of  a  picture 
interval  and  running  sixteen  pictures  per  second,  if  desired. 

Pin.  Pin  intermittent  movements  are  those  in  which  the  teeth 
engaging  the  holes  in  the  film  are  not  the  teeth  of  a  sprocket  wheel, 
but  are  teeth  fixed  to  some  reciprocating  member  which  gives  them 
the  four  movements  necessary  to  control  the  film  with  pins,  namely, 
(1)  to  advance  the  pins  into  the  holes  of  the  film,  (2)  to  move  down- 
ward, dragging  the  film,  (3)  to  withdraw  the  pins  from  the  holes  in 
the  film,  and  (4)  to  return  to  the  point  of  starting  in  readiness  for 
advancing  into  the  next  holes  of  the  film  to  repeat  the  cycle. 


Fig.  20.      Theory  of  Pin 
Intermittent  Movement 


109 


36 


THE  MOTION  PICTURE 


Fig.  20  shows  the  theory  of  such  a  film  movement.  The  pins 
P  are  carried  vertically  by  the  action  of  the  crank  C  of  the  steady 
drive  shaft  D,  which  shaft  carries  also  the  cam  wheel  R  in  the  edge 
of  which  is  a  groove  which  controls  the  pins  P  for  their  lateral  move- 
ment, advancing  them  into  the  film  holes  and  withdrawing  them  as 
required.  The  slot  of  the  cam  wheel  R  is  straight  except  in  tw^o  places, 
for  advancing  and  retreating  the  pins,  one  of  the  inclined  places  of 
the  cam  slot  being  shown  in  the  figure  just  above  the  level  of  the  pins 
P.    The  adjustment  of  the  cam  wheel  R  and  the  crank  C  with  angular 


KA 


A 


o  o 


3 


d' 
k 


g 


Fig.  21.     Pin  Intermittent  Movement  Taking  the  Four  Movements  from  One  Cam 

relation  to  each  other  is  such  that  the  pins  C  are  shoved  into  the 
holes  of  the  film  by  the  cam  wheel  R  just  as  the  pins  come  to  rest  at 
their  upper  limit  of  movement,  and  they  are  withdraw^n  just  as  they 
come  to  rest  in  their  lower  limit  of  movement.  The  time  of  motion 
of  the  film  is,  therefore,  just  one-half  the  total  picture  time,  the  film 
remaining  at  rest  during  the  remaining  half  of  the  picture  interval. 


110 


« 


MOTION  HEAD 


37 


Another  design  of  pin  movement,  suitable  either  for  the  direct 
action  of  the  pin  upon  the  fihn  or  for  action  of  the  pins  upon  a  sprocket 
shaft  for  intermittent  sprocket  motion,  is  shown  in  Fig.  21,  which 
iUustrates  the  device  in  four  of  its  positions  of  operation,  and  shows 
it  equipped  for  driving  a  sprocket  shaft  intermittently.  The  sprocket 
shaft,  or  intermittent  shaft,  is  shown  with  six  pins,  and  the  teeth  of 
the  intermittent  driving  movement  are  show^n  near  the  middle  of 
each  of  the  figures.  The  triangular  cam  is  the  steady  drive  member 
of  the  device,  and  it  has  such  form  that  it  fits  the  four  sides  of  the 
square  surrounding  it  at  all  times.  In  the  upper  left-hand  drawing, 
the  teeth  are  withdraw^n  from  the  pin  of  the  intermittent  wheel; 
in  the  upper  right-hand  drawing, 
the  triangular  cam  has  turned 
and  has  advanced  the  teeth  to 
enclose  one  of  the  pins  upon 
the  intermittent  wheel,  which  as 
yet  has  not  been  moved;  in  the 
lower  left-hand  drawing,  the  tri- 
angular cam  has  moved  further 
and  has  lifted  the  teeth  enclosing 
the  pin  of  the  intermittent  wheel, 
thereby  driving  the  intermittent 
wheel  through  one-sixth  of  its  rev- 
olution; in  the  lower  right-hand 
drawing  the  triangular  cam  has 
moved  further  and  has  with- 
drawn the  pins  from  engagement 
with  the  pin  of  the  intermittent 
wheel,  and  is  in  readiness  to  be  lowered  into  the  position  shown  in 
the  upper  left-hand  drawing,  to  repeat  the  cycle. 

Another  type  of  pin  movement  is  shown  in  Fig.  22,  where  the 
action  is  attained  by  two  cams.  The  pin  pair  is  located  at  the  top 
of  the  vertical  lever  upon  the  wrist  pin,  which  drives  it  vertically 
as  a  pitman  rod,  but  at  the  same  time  the  top  of  the  vertical  pin  lever 
is  rocked  to  the  right  and  to  the  left,  as  view^ed  in  the  figure,  by  the 
arm  which  is  attached  to  it  near  the  pins  at  the  top  and  which  passes 
to  the  right.  By  means  of  this  auxiliary  cam  connection,  the  pins 
are  advanced  into  the  film  holes  when  the  lever  is  at  the  upper  limit 
of  its   stroke   and   are   withdrawn  when  it   is  at  the    lower    limit. 


Fig. 


Pin  Intermittent  Movement 
from  Two  Cams 


111 


38 


THE  INIOTION  PICTURE 


Still  another  type  of  pin  movement  acting  directly  into  the  film 
holes  is  shown  in  Fig.  23.     The  two  cams  are  upon  one  shaft,  one, 


Vwy 


Fig.   23. 


Pin  Intermittent  Movement  Taking  the  Foiir  Movements 
from  Two  Cams  on  the  Same  Shaft 


a    triangular    cam,    providing    for  the  Aertical  movement,  and    the 

other  a  circular  cam,  providing  for  the 
movement  toward  and  from  the  plane  of 
the  film.  These  cams  take  the  proper 
angle  on  the  shaft  to  provide  for  insert- 
ing the  pins  into  the  film  holes  while  the 
pins  are  at  rest  in  their  vertical  movement. 
Claw.  The  principle  of  the  claw  in- 
termittent movement  is  shown  in  Fig.  24. 
In  this  figure,  S  is  the  film  with  perforated 
edges,  preferably  only  one  hole  per  picture ; 
D  is  the  steady  drive  shaft,  P  a  pitman 
rod,  R  a  reciprocating  frame  carrying  the 
claw,  and  C  the  claw  itself.  The  opera- 
tion is  merely  that  of  a  pawl  upon  a  rack 
or  ratchet,  the  film  being  the  ratchet  or 
rack  and  the  holes  being  the  spaces  be- 
tween the  teeth  for  thv  claw  or  pawl  to  engage.    As  the  pitman  rod 


112 


Fig.   24.     An  Intermittent 

Mechanism  Built  Upon 

the  Claw  Principle 


4 


MOTION  HEAD 


39 


draws  the  reciprocating  frame  up,  tlie  claw  rides  on  the  edge  of  the 
hole  until  lifted  out  of  tiie  hole,  then  it  rides  upon  the  film  under 
pressure  of  its  spring  until  it  reaches  the  next  hole,  when  it  drops  in. 
When  the  pitman  then  drives  the  reciprocating  frame  down,  the 
claw  drags  the  film  down,  and  again  rides  up  to  the  next  hole. 

The  pin  and  claw  movements  both  are  very  severe  in  wear 
upon  the  holes  of  the  film.  They  are  suitable  for  cameras  where 
the  film  is  passed  through  the  machine  but  once;  frequently  they  are 
found  on  projecting  machines  of  an  older  type. 

Beater.  The  principle  of  the  beater  intermittent  movement  is 
that  the  film  shall  be  taken  up  constantly,  and  at  a  constant  rate, 


Fiff.  25.     An  Intermittent  Merhanism  of  ilie  Beater  Type 


but  that  there  shall  be  a  definite  amount  of  slack  pulled  through 
the  film  gate  into  a  lower  film  loop  just  below  the  film  gate,  this 
slack  being  pulled  through  once  for  each  picture  interval,  to  shift 
the  picture  in  the  film  window.  The  amount  of  slack  in  the  film  loop 
between  the  film  gate  and  the  steady  drive  take-up  wheel  shall  be 
greater  than  the  picture  length  of  the  film,  so  that  the  take-up  wheel 
never  pulls  directly  upon  the  film  at  the  film  gate  but  acts  only  to 


113 


40 


THE  MOTION  PICTURE 


5- 


take  up  the  slack  pulled  in  by  the  beater.  The  beater  may  be  a 
wrist  pin  upon  a  face  plate,  or  it  may  be  a  spring-propelled  or  pitman 
propelled  device,  or  any  reciprocating  part  whatsoever. 

IVrist-Pin  Type.  The  wrist-pin  type  of  beater  intermittent 
movement  is  shown  in  Fig.  25.  The  steady  drive  wheel  is  shown 
as  a  drum  at  D  with  the  presser  roller  P.  The  beater  pin  B  is  upon 
the  face  of  the  wheel  B'  and  the  wheels  B'  and  D  are  geared  together 
by  a  pair  of  spur  gears.  As  the  pin  B  passes  over  the  top  of  its  travel, 
the  wheel  or  drum  D  takes  up  the  slack  between  D  and  G,  or  takes 
up  a  definite  measure  of  the  slack,  although  perhaps  not  all  of  it. 
Then  as  pin  B  passes  downward  it  pulls  upon  the  film  and  draws 
through  the  film  gate  G  just  as  much  as  has  been  taken  up  by  the 
drum  D  since  the  last  pull.  The  amount  of  film  pulled  through 
the  film  gate  G  does  not  depend  upon  the  size,  character,  position, 
or  radius  of  rotation  of  the  beater  pin  B,  but  does  depend  upon  the 
amount  of  rotation  of  the  drum  D ,  or  the  amount  of  lineal  travel  of 
the  surface  of  the  drum  D  for  each  revolution  of  the  beater  pin  B. 

Pitman  Type.  The  pitman  type  of 
beater,  illustrated  in  Fig,  26,  shows  the 
beater  mechanism  alone.  The  film  *S  is 
shown  as  a  heavy  line  from  top  to 
bottom  of  the  figure,  ben't  between  the 
two  fixed  studs,  A  and  C,  which  may  be 
merely  idler  rollers,  by  the  thrust  of  the 
beater  roller  B.  The  beater  roller  B  is 
carried  upon  the  pitman  rod  D  which  is 
driven  by  the  crank  E  upon  the  steady 
drive  shaft  F.  The  film  gate  of  the 
figure  is  assumed  to  be  above  the 
mechanism  of  the  figure,  and  the  steady  drive  take-up  device  is 
assumed  to  be  below,  taking  up  between  shifts  the  slack  pulled  into 
the  film  by  the  beater  roller  B,  or  at  least  a  part  of  that  slack.  In 
this  device,  as  in  all  beater  devices,  the  amount  of  film  drawn  into  the 
film  gate  by  the  action  of  the  beater  roller  is  not  dependent  upon  the 
characteristics  of  the  beater  roller  or  of  the  fixed  studs  co-operating 
with  it,  but  depends  solely  upon  the  amount  of  film  travel  over  the 
take-up  drum  during  a  single  revolution  of  the  steady  drive  shaft  F. 
Spring- Bar  Type.  Tlie  spring-bar  beater  is  still  another  type 
of  beater  intermittent   mechanism.     It  consists  of  a  beater  roller 


Fig.  26.     The    Pitman    Type  of 
Beater  Intermittent  Mechanism 


114 


MOTION  HEAD 


41 


mounted  upon  a  spring-pressed  bar,  which  bar  is  restrained  by  a 
ratchet  mechanism  until  the  shift  is  desired,  when  it  is  released  to 
strike  the  film  so  as  to  draw  the  slack  into  the  film  loop,  being  im- 
mediately picked  up  by  its  restraining  mechanism  again,  and  again 
held  until  the  instant  of  the  next  shift. 

Intermittent  Grip.  The  intermittent  grip  mechanism,  shown 
in  Fig.  27,  is  in  a  class  by  itself,  but  never  has  come  into  general  use. 
It  operates  without  perforations  in  the  film.  The  two  wheels  revolve 
toward  each  other,  and  when  the  enlarged  places  meet  with  the  film 
between  them,  the  film  is  gripped  and  drawn  downward  through 
the  film  gate.     The  amount  of  film  pulled  at  each  such  meeting, 


Fig.  27.     Intermittent  Grip  Mechanism 

that  is,  at  each  revolution  of  the  pair  of  grip  wheels,  depends  upon 
the  length  of  the  gripping  surfaces  which  meet  each  other.  Framing 
is  accomplished  by  shifting  the  rollers  slightly  so  that  their  ends 
overlap,  the  extending  ends  not  being  effective  in  pulling  the  film, 
and  thus  reducing  the  amount  pulled. 

For  the  greater  part,  all  mention  of  intermittent  mechanisms 
other  than  the  intermittent  sprocket  feeds  are  historical,  the  sprocket 
being  almost  universal  at  the  present  time  for  projecting  machines; 
many  of  the  variations  in  intermittent  mechanisms,  and  particularly 
in  pin  mechanisms,  are  found  in  cameras  for  taking  motion  pictures. 


115 


42  THE  MOTION  PICTURE 

Adjustment  of  Intermittent  Movements.  The  customary  ad- 
justment provided  for  the  internu'ttent  movements  for  taking  up 
wear  lietween  the  wheels  or  cams  is  the  eccentric  bushing.  This 
bushing,  which  is  inckided  as  a  part  D  of  Fig.  9,  is  placed  in  the 
hole  in  the  frame  through  which  the  drive  shaft  of  the  intermittent 
movement  passes,  and  the  drive  shaft  itself  passes  through  the  hole 
in  the  bushing,  indicated  by  the  small  dotted  circle.  By  turning  the 
bushing  slightly  in  the  frame,  the  position  of  the  drive  shaft  is  changed 
verv  slightly  as  compared  with  the  movement  of  the  bushing,  and 
a  very  accurate  adjustment  is  possible.  The  cams  should  be  adjusted 
when  properly  oiled  with  a  medium  heavy  oil — a  very  light  oil  will 
not  stav  on  the  cams  and  a  very  heavy  oil  is  too  sticky  for  the  rapid 
cam  motion.  If  adjusted  dry,  there  will  not  be  room  for  the  oil  to 
work  between  the  cam  surfaces  without  making  the  adjustment 
too  tight,  and  if  adjusted  with  a  surplus  of  oil  the  oil  will  work  away 
and  leave  them  loose.  The  adjustment  of  the  cam  band  of  the  pin 
wheel  and  the  concave  wing  of  the  star  wheel  must  be  very  accurate 
or  the  picture  will  lose  its  steadiness  on  the  screen,  taking  a  slight 
vertical  jiggle.  Many  Geneva  movements  are  fitted  with  an  "oil 
box  or  tank  and  run  immersed  in  oil. 

The  pin  and  claw  movements  must  be  kept  carefully  adjusted, 
particularly  as  to  those  cams  which  give  the  film  the  vertical  move- 
ment. The  film  teeth  of  these  mechanisms  wear  rapidly  and 
should  be  examined  frecjuently  a!id  replaced  when  wear  is  detected. 

In  the  beater  type  of  mechanism,  the  beater  roller  usually  is 
cut  away  in  the  middle  and  strikes  the  film  only  on  the  edges,  outside 
of  the  picture  space.  With  rollers  thus  cut  away  in  the  middle,  the 
remaining  bosses  which  strike  the  film  are  likely  to  become  worn 
conical,  tapering  toward  the  inside,  resulting  in  irregular  action  of 
the  film  and  consequent  jiggling  on  the  screen.  In  adtlition,  a  worn 
beater  roller  wears  the  film  by  bending  it. 

The  edges  of  the  celluloid  film  in  the  holes  engaged  by  the 
sprocket  teeth  or  pins  or  claws  are  sharp  and  hard  enough  to  cut 
away  the  teeth  which  grip  them  and  particularly  because  of  the 
rapidity  and  of  the  almost  innumerable  times  that  the  film  is  gripped, 
j)ulled,  and  loosened  in  the  course  of  a  few  months'  use  of  a  project- 
ing machine  in  a  theater.  Wear  of  the  teeth  engaging  the  film  acts 
upon  the  film,  for  the  teeth  wear  into  a  hollow  on  the  pulling  face, 


116 


II 


MOTION  HEAD  43 

making  the  point  of  the  tooth  of  sHghtly  liooked  shape,  and  these 
hook  teeth  pull  against  the  edge  of  the  holes  and  tend  to  tear  the  film 
as  they  leave  it.  Worn  teeth  must  l)e  watched  for  and  replaced  when 
noticed. 

Sprocket  wheels  are  interchangeable,  and  new  ones  can  be 
bought  from  the  projection  machine  makers  and  placed  on  the  motion 
head  with  little  trouble,  or  new  rings  of  teeth  can  be  bought  and 
placed  upon  the  old  sprocket  drums  or  bosses.  Some  types  of  sprock- 
ets are  especially  constructed  with  interchangeable  teeth,  and  new 
tooth  rings  may  be  bought  at  a  very  low  price  to  replace  the  worn 
ones. 

In  addition  to  watching  for  wear  and  loose  adjustments,  the 
moving  mechanism  of  the  intermittent  and  all  other  parts  of  the 
motion  head  should  be  cleaned  periodically,  say,  every  two  months 
if  the  machine  is  running  evenings  only  and  is  giving  no  trouble, 
and  every  two  weeks  or  every  month  if  the  machine  is  running  all 
day,  even  though  giving  perfect  service,  and  with  no  indication  of 
trouble.  Wipe  off  all  oil,  and  empty  the  oil  bath  of  the  intermittent 
movement  if  it  has  one.  Run  the  intermittent  tank  full  of  gasoline 
and  turn  the  machine  for  a  while  to  work  it  thoroughly  through  the 
cams;  of  course  it  will  work  out  through  the  journals  of  the  oil  box 
and  wash  those  clean.  Wipe  it  off  as  it  comes  out,  using  a  clean  rag. 
Next,  the  mechanism  should  be  oiled  liberally  with  a  very  light  oil 
to  wash  out  the  residue  of  the  evaporated  gasoline,  and  this  light 
oil  then  should  be  followed  with  the  standard  body  of  oil  regularly 
used  on  the  machine.  The  gasoline  (or  even  kerosene)  loosens  the 
dirt,  the  light  oil  carries  out  what  the  gasoline  left  by  its  too  rapid 
evaporation,  and  the  journals  then  are  clean  and  ready  for  their 
standard  working  dose  of  regular  lubrication.  Do  the  same  for  all 
of  the  journals,  putting  oil  in  the  oil  holes  with  a  can  spout  and 
wiping  it  off  as  it  runs  through — first  gasoline,  then  very  thin  oil, 
then  regular  lubricator — loosen  the  dirt,  wash  it  out,  then  oil  up  for 
service.  The  toothed  surfaces  of  the  gear  wheels  should  be  cleaned 
in  the  same  way,  for  they  pick  up  grit  very  freely.  If  after  cleaning 
the  gear  wheels  they  rattle  a  little,  wipe  them  as  dry  as  possible  and 
hold  a  lump  of  beeswax  against  the  teeth  and  turn  the  handle  of  the 
motion  head  through  several  revolutions.  This  will  quiet  the  noise 
without  injuring  the  gears. 


117 


44 


THE  MOTIOxV  PICTURE 


CONTINUOUS  PROJECTION 

Any  system  which  will  keep  the  illumination  constant  upon 
the  screen  will  be  independent  of  the  disadvantages  of  flicker,  and 
possibly  other  disadvantages  may  be  avoided  or  disadvantages 
obtained  by  devices  designed  to  project  the  second  picture  upon 
the  screen  before  the  first  is  removed,  as  with  the  dissolving  lantern. 

Four  methods  of  attack,  none  of  which  has  come  into  general 
use,  have  been  used  for  this  problem,  viz,  duplex  projection,  moving 
lenses,  moving  mirrors,  and  moving  prisms. 


II 
II 
i! 
I! 

f 


r~\ 


Fig.   28.     Duplex  Projection 


\y 


Fig.   29.     Continuous  Projection  by 
Moving  Lenses 


Duplex  Projection.  Duplex  projection  consists  of  projecting 
from  two  lanterns  with  a  dissolving  shutter,  each  change  dissolving 
from  the  old  picture  to  the  new,  and  each  lantern  shifting  its  film 
to  the  succeeding  picture  while  the  viewing  screen  is  under  full 
illumination  from  the  companion  lantern. 

The  arrangement  of  the  two  lanterns  driven  by  one  motor  is 
shown  in  Fig.  28,  the  lanterns  indicating  by  the  dotted  lines  that  the 
central  rays  projected  reach  the  same  point  upon  the  picture  screen. 
At  the  right  of  the  lantern  diagram  is  seen  the  front  view  of  the 


118 


MOTION  HEAD 


45 


before-the-lcns  shutter  M  which  is  pLaced  between  the  two  lanterns 
and  acts  as  shutter  for  both  of  them.  The  white  half  is  the  open 
half,  the  dark  quarter  is  opaque,  and  the  remaining  portions  are 
semi-transparent.  These  semi-transparent  portions  of  the  shutter 
extend  the  dissolving  of  the  view  and  make  it  a  little  softer  than  a 
simple  half-and-half  shutter  would  give. 

Moving  Lenses.  jNIoving  lenses  for  continuous  projection  are 
shown  in  Fig.  29,  which  is  a  front  view  of  the  projecting  machine. 
The  lenses  of  the  chain  are  spaced  |  inch  apart — just  picture  dis- 
tance— and  each  of  them  follows  a  picture  down  as  the  film  passes 


Fig.  30.     Continuous  Projection  by  Moving  Mirrors 

with  steady  motion  through  the  film  window,  which  is  nearly  as  long 
as  two  pictures.  There  is  no  intermittent  mechanism  in  this  pro- 
jector. The  middle  lens  at  the  left  of  the  chain  is  shown  in  the 
middle  of  the  projection  window,  and  as  the  lens  now"  visible  through 
that  window  passes  downward  with  its  film  image,  the  next  lens 
will  approach  the  projecting  window  from  the  top.  The  top  and 
bottom  edges  of  the  projecting  windows  are  substantially  shutter 
edges,  and  as  the  following  lens  comes  into  action  at  the  top  of  the 
window,  the  preceding  lens  will  go  out  of  action  by  passing  behind 
the  lower  edge  of  the  window.  Thus,  a  dissolving  effect  is  secured, 
and  continuous  illumination  of  the  screen  is  effected,  changing  the 
images  without  intermittent  mechanical  motion. 


119 


46 


THE  MOTION  PICTURE 


Moving  Mirrors.  Moving  mirrors  for  continuous  projection  are 
shown  in  diagrammatic  perspective  in  Fig.  30.  The  large  vvlieel  is  a 
wheel  of  shutter  leaves,  carrying  the  picture  film  upon  its  surface,  or 
upon  the  edges  of  the  shutter  leaves  which  form  a  series  of  windows  over 
which  the  pictures  of  the  film  are  stretched.  In  the  center  of  the  wheel 
is  a  drum  of  mirrors  which  is  arranged  to  turn  at  half  the  speed  of  the 
drum  of  shutters  carrying  the  film  strip  and  pictures.  At  the  left  is  the 
lamp  house  and  the  dotted  lines  show  the  course  of  the  beam  of  light 


;^^^^•y^.^^^'-^^^^^^^^^^^^^y^'^ 


^V^^^V-  V^'.V^^^V-vV.^W.WJ 


Fig.  31.     Projecting  Machine  for  Continuous  Projection  by  M 


oving  Prism 


from  the  lamp  house  through  the  condensers  in  the  front  of  the  house, 
through  the  film,  through  the  single  lens  to  the  drum  of  mirrors,  then 
to  a  fixed  mirror  and  then  downward,  whence  the  beam  carries  to  the 
picture  screen.  Again  there  is  a  continuous  illumination  of  the  screen 
without  any  intermittent  mechanism.  Two  mirrors  of  the  drum  in  the 
center  always  will  be  working  in  the  beam  of  light  between  the  lamp 
house  and  the  screen,  one  mirror  projecting  the  upper  and  the  other 
the  lower  portion  of  the  picture  seen  upon  the  screen,  except  at  the 
instant  when  one  mirror  ceases  and  another  begins  the  projection. 


120 


^rOTTOX  HEAD 


47 


Moving  Prisms.  Moving  prisms  for  continuous  projection  are 
shown  in  Figs.  31  and  32.  Fig.  31  shows  the  diagram  of  the  com- 
plete projecting  machine  from  condensers  to  objective  lens,  and  Fig. 
32  shows  two  diagrams  disclosing  the  course  of  the  rays  forming  the 
beam  of  light  through  the  film,  prism,  and  olijective  lens.  No  inter- 
mittent mechanism  is  used. 

Steady  Feed  Elements.  The  motion  head  projecting  by  inter- 
mittent motion  of  the  film  is  provided  with  two  elements  of  steady 
feed  for  relieving  the  film  from  the  jerk  of  the  intermittent  as  far  as 
possible.  If  the  intermittent  feed  were  required  to  pull  the  film  from 
the  feed  reel,  turning  the  reel  in  so  doing,  and  if  also  the  take-up 
reel  were  allowed  to  pull  directly  upon  the  teeth  of  the  intermittent 
sprocket,  the  wear  upon  the  film  and  upon  the  sprocket  would  be 


^.c 


Fig.    32. 


Diagrams  of  Course  of  Light  Rays  in  Continuotis 
Projection  by  Means  of  Moving  Prism 


great.  This  is  much  reducerl  by  providing  upper  and  lower  steady 
feed  sprockets,  relieving  the  intermittent  mechanism  from  all  duty 
but  the  shift  of  the  short  piece  of  film  in  the  film  gate,  the  film  being 
brought  from  the  feed  reel  down  to  the  upper  end  of  the  film  gate 
by  the  upper  steady  feed  sprocket,  and  being  held  slack  below  the 
intermittent  and  fed  to  the  take-up  reel  under  proper  tension  by  the 
lower  steady  sprocket.  In  order  that  a  proper  looseness  of  film, 
or  slack  to  avoid  strains,  may  be  had  above  and  below  the  inter- 
mittent feed,  the  film  is  formed  in^o  slack  bends  which  are  known 
as  upper  feed  loops  and  loicer  feed  loops. 


121 


'48  THE^MOTIOX  PICTURE 

THREADING  UP  THE  MOTION  HEAD 

The  course  of  the  fihn  through  the  motion  head,  the  elements 
which  operate  upon  it,  and  the  method  of  placing  the  film  in  position 
may  be  studied  at  the  same  time,  taking  the  steps  in  the  order  in 
which  they  are  encountered  by  the  film  in  its  travel. 

Feed  Reel.  The  feed  reel  is  a  spool  upon  which  the  picture  film 
strip  is  wound  when  ready  for  projection.  It  consists  of  a  core  from 
H  to  2^  inches  in  diameter,  with  a  spring  clip  for  taking  the  end  of 
the  film  which  is  to  be  the  inside  end  of  the  reel;  the  reel  then  is  turned 
and  the  film  is  wound  upon  it,  a  strip  of  1,000  feet  of  film  filling  the 
reel  to  a  total  diameter  of  about  10  inches.  The  10-inch  reel  has 
upon  its  core  two  sheet-metal  flanges  equivalent  to  spool  ends,  which 
are  about  10  inches  in  diameter.  Winding  the  spool  full  of  the  film 
to  be  projected,  beginning  with  the  "end  of  the  picture"  or  "tail" 
of  the  film,  and  finishing  with  the  "title"  of  the  picture  or  "leader" 
of  the  film  upon  the  outside  of  the  spool,  is  called  rewinding,  and 
when  so  wound,  or  rewound  it  is  ready  to  be  placed  in  position. 

Feed=Reel  Magazine.  An  iron  fireproof  box  with  a  fire-trap 
film  outlet  is  provided  for  receinng  the  feed  reel.  The  feed  reel, 
in  response  to  the  pull  upon  the  film  by  the  upper  steady  feed,  turns 
loosely  in  this  fireproof  magazine.  Place  the  full  feed  reel  in  the  upper 
magazine,  start  the  lead  end  of  the  film  through  the  film  outlet  at 
the  bottom  of  the  feed  magazine,  just  above  the  motion  head,  and 
close  and  fasten  the  feed  magazine  door.  The  feed  reel  is  shown 
without  its  fireproof  magazine  at  1  in  Fig.  33. 

Upper  Steady  Feed.  The  lead  end  of  the  film  is  pulled  out  about 
3  feet,  the  presser  roller  is  lifted  from  the  upper  steady  feed  sprocket 
and  the  film  is  laid  upon  the  surface  of  the  sprocket  drum  with  the 
teeth  of  the  sprocket  passing  properly  through  the  holes  in  both 
edges  of  the  film.  The  presser  roller  is  dropped  upon  the  drum  with 
its  spring,  or  there  may  be  two  such  presser  rollers,  or  an  idler  roller 
between  the  upper  feed  and  the  feed  reel.  In  Fig.  14,  an  idler  roller 
is  shown  at  2  to  direct  the  film  to  the  upper  steady  feed  sprocket  3 
at  the  top  of  the  sprocket  so  that  the  film  will  wrap  a  full  half-way 
around  the  sprocket  and  get  the  benefit  of  a  pull  by  a  large  number 
of  the  sprocket  teeth.  The  presser  roller — or  friction  roller  as  it  is 
sometimes  called,  though  friction  is  no  part  of  its  function— is  shown 
by  the  small  circles  just  below  the  sprocket  3,  not  numbered. 


122 


=  ^ 


a 

2'  = 
>  ^^  =» 

o  Sis 

W 

H 

<; 
[I. 

H  '.^ 

A  ^  a, 

a  e 

Pi 

O 

M    So 

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s 

&     C"i 

o  gg 

M 
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o  Z 


MOTION  HEAD 


49 


Upper  Feed  Loop.  The  film  is  formed  into  the  upper  feed  loop 
before  passing  to  the  film  gate,  that  is,  the  film  gate  is  opened  and 
the  film  is  placed  in  the  groove  of  the  body  of  the  gate,  the  film  being 
lifted  from  2  to  6  inches  higher  in  the  gate  than  it  would  be  if  stretched 
straight  from  the  top  steady  feed  sprocket  to 
the  gate.  The  film  in  the  gate  is  carried 
into  engagement  with  the  intermittent 
sprocket  teeth,  and  the  door  of  the  film  gate 
is  closed  upon  it,  clamping  it  in  position. 
The  placing*  of  the  film  higher  in  the  film 
gate  leaves  a  looseness  in  the  film  above  the 
film  gate  and  between  the  film  gate  and  the 
upper  steady  feed  sprocket,  which  forms  the 
upper  feed  loop,  as  shown  at  4  in  Fig.  33. 
At  every  shift,  the  intermittent  feed  pulls 
some  of  the  slack  out  of  this  loop,  and 
between  shifts  the  upper  steady  feed  feeds 
the  film  down  to  replenish  the  slack  pulled 
out  by  the  intermittent. 

Film  Steady  Drum.  In  some  motion 
heads  the  film  is  not  permitted  to  feed 
directly  from  the  upper  feed  loop  to  the 
film  gate,  but  is  taken  over  a  drum  which 
guides  it  into  the  entrance  to  the  gate.  This 
film  steadier  is  shown  at  5  in  Fig.  33,  and 
its  presser  roller  is  shown  by  the  small  cir- 
cles just  above  the  drum  5. 

Film  Gate.  The  film  gate  is  indicated 
at  G  in  Fig.  33.  It  is  of  many  types,  but 
usually  has  a  door  to  be  opened,  and  a  groove 
into  which  the  film  is  laid  and  upon  which 
the  door  is  then  closed. 

Intermittent  Sprocket.  The  teeth  of  the 
intermittent  sprocket  or  of  the  intermittent 
feed  of  any  type  usually  are  so  closely  associated  with  the  film  gate 
that  they  substantially  run  in  the  sides  of  the  groove  through  the 
body  of  the  film  gate,  so  that  at  one  operation  the  film  strip  is  placed 
in  the  groove  of  the  gate  and  upon  the  teeth  of  the  intermittent 


^ig.  33.     Dia^am  Showing 

Film-Feeding  Elements  of 

tlie  Motion  Head 


123 


50  THE  MOTION  PICTURE 

mechanism.  The  intermittent  sprocket  is  shown  at  7  in  Fig.  33,  and 
its  presser  roller  is  shown  by  the  small  circles  just  below  it. 

Lower  Feed  Loop.  The  lower  loop  is  formed  as  the  upper  loop 
was,  by  placing  the  film  upon  the  lower  steady  feed  sprocket  from 
2  to  6  inches  higher  than  it  would  lie  if  drawTi  straight  from  the 
intermittent  mechanism  (jr  film  gate.  The  lower  feed  loop  is  shown 
at  8  in  Fig.  33.  The  intermittent  pulls  three-ciuarters  of  an  inch  of 
film  into  this  louver  loop  at  every  shift  of  the  pictures,  thereby  increas- 
ing the  size  of  the  loop,  but  the  lower  steady-feed  sprocket  takes 
the  film  up  steadily  and  takes  up  the  exact  amount  of  film  before 
the  next  shift. 

Lower  Steady=Feed  Sprocket.  This  sprocket  is  shown  at  0  in 
Fig.  33,  and  its  presser  roller  is  shown  by  the  small  circles  just  above 
it.  In  this  figure  the  presser  rollers  of  the  upper  steady  sprocket 
and  of  the  friction  drum  are  placed  upon  the  same  arm,  while  the 
presser  rollers  of  the  lower  steady  sprocket  and  of  the  intermittent 
sprocket  also  are  upon  the  same  arm — this  is  a  matter  of  preference 
and  convenience  for  the  operator  as  differently  designed  by  the 
different  manufacturers.  The  film  now  is  taken  over  the  idler  W 
— which  is  omitted  in  some  motion  heads— to  the  take-up  reel. 

Take=L'p  Reel.  This  is  substantially  the  same  as  the  feed  reel. 
If  the  end  of  film  leader  which  was  drawTi  out  of  the  feed  magazine 
to  begin  threading  is  not  long  enough  to  reach  the  take-up  reel,  the 
handle  of  the  motion  head  may  be  given  a  few  turns,  feeding  the  film 
down.  The  end  is  passed  into  the  take-up  magazine  through  the  film 
outlet  (which  is  an  inlet  this  time)  and  the  end  is  fastened  under 
the  spring  clip  upon  the  hub  of  the  take-up  reel.  I'he  slack  of  the 
film  between  the  take-up  reel  and  the  lower  steady  feed  is  wound 
up  by  turning  the  spool  itself  by  hand,  then  the  motion-head  handle 
is  given  a  turn  or  two  with  the  take-up  magazine  door  open  in  order 
to  make  sure  that  the  take-up  is  working  properly.  Then  the  door 
of  the  take-up  magazine  is  closed  and  you  are  ready  to  light  up, 
start  the  crank,  open  the  fire  shutter,  and  "let  'er  flicker" — for  slang 
ceases  to  be  slang  when  it  is  simple  truth. 

The  take-up  must  be  watched  particularly  at  the  beginning  of 
the  film  reel,  and  particularly  toward  the  end  of  the  film  reel,  when 
the  take-up  reel  is  nearly  full,  is  heavy  to  move,  and  moves  slowly 
on  account  of  the  long  distance  around  it.     The  take-up  reel  moves 


124 


MOTION  HEAD  51 

more  and  more  slowly  as  the  spool  gets  more  and  more  nearly  full, 
and  some  compensation  is  required  between  the  speed  of  the  reel, 
always  varying,  and  the  speed  of  the  driving  handle,  which  is 
constant.  This  compensation  usually  is  provided  by  a  friction  drive 
for  the  take-up  reel — perhaps,  a  pair  of  friction  plates  held  together 
by  a  spring;  perhaps,  two  grooved  wheels  belted  by  a  belt  which  is 
supposed  to  pull  tight  enough  to  pull  the  heaviest  load  and  yet  slip 
rather  than  tear  the  film  or  stop  the  operator's  arm.  These  friction 
devices  should  be  noted  and  kept  in  proper  adjustment,  for  a  friction 
device  can  hardly  be  expected  to  stay  in  adjustment  very  long,  as 
the  plates  wear  smooth  or  get  grit  between  them,  and  the  belts  stretch. 
The  friction  device  must  drive  the  take-up  reel  fast  enough  to  take 
up  the  film  on  its  small  center  when  the  film  is  just  starting,  and 
must  not  pull  so  hard  that  it  will  pull  the  film  apart  in  its  weaker 
spots.    Excess  friction  makes  the  handle  turn  harder. 

Framing  Devices.  The  word  "frame"  when  applied  to  the 
projection  of  motion  pictures  refers  to  the  position  of  the  projected 
image  upon  the  picture  screen,  or  to  the  position  of  the  film  image 
as  related  to  the  film  windows.  "When  the  top  of  the  picture  is  at 
the  top  of  the  screen,  or  at  the  bottom  of  the  film  window,  and  the 
picture  just  fills  the  screen  and  the  window,  the  picture  is  said  to  be 
"in  frame,"  tlie  image  fitting  the  film  window  as  the  lithograph  fits 
the  frame  on  the  cottage  wall.  Wnen,  by  reason  always  of  improper 
adjustment  of  the  film  or  of  the  motion  head,  the  top  of  the  picture 
on  the  screen  is  a  few  inches  from  the  top  of  the  illuminated  area 
upon  the  screen,  and  the  lower  edge  of  the  next  picture  shows  across 
the  top  of  the  picture  being  projected,  then  the  picture  is  said  to  be 
"out  of  frame,"  and  when  examined  in  the  film  window  it  will  be 
seen  that  the  little  image  does  not  register  with  the  window.  As 
films  may  be  defective  in  median  portions,  the  motion  head  must 
be  able  to  frame  while  running. 

Framing  is  accomplished  by  shifting  the  film  with  reference 
to  the  lens  or  film  window.  Somewhere  about  the  motion  head — 
and  its  position  and  general  appearance  varies  with  different  makes 
of  machines —will  be  found  a  framing  lever,  ^^^len  the  motion  head 
is  standing  at  rest,  and  when  the  framing  lever  is  moved,  {!)  the  lens 
and  film  window  will  move  upward  or  downward  with  the  film  remain- 
ing stationary  in    the   gate;    or  {2)  the    film   gate    and    intermittent 


las 


52  THE  MOTION  PICTURE 

mechanism  as  a  whole  will  move  upward  or  downward,  the  lens 
remaining  stationary;  or  (5)  the  intermittent  feed  alone  will  move 
as  a  whole  and  will  draw  the  film  downward  or  try  to  push  it  upward 
through  the  film  gate;  or  (4)  the  intermittent  sprocket  will  rotate  a 
little  in  one  direction  or  the  other,  without  changing  the  location  of 
its  shaft;  or  (-5)  a  little  slack  will  be  taken  up  or  let  out  in  &  framing 
loop  formed  for  the  purpose  of  framing,  and  located  between  the 
intermittent  feed  mechanism  and  the  film  window. 

Framing  is  usually  and  most  easily  accomplished  by  looking 
at  the  picture  projected  upon  the  screen.  The  picture  may  be  brought 
approximately  to  frame  by  looking  at  the  film  window  after  thread- 
ing up  the  head  and  before  beginning  projection.  The  final  adjust- 
ments, like  the  final  adjustments  of  focus,  should  be  made  by  watch- 
ing the  picture  screen  during  projection. 

The  framing  lever  always  has  a  movement  of  more  than  one 
full  picture.  When  you  try  to  "frame  up"  and  the  lever  will  not 
move  far  enough  to  frame  the  picture,  then  "frame  down"  nearly 
a  whole  picture  instead  and  the  proper  adjustment  can  be  reached. 

Rewinding.  When  the  reel  of  film  has  been  turned  through, 
the  tail  end  is  allowed  to  run  through  to  the  lower  steady  feed,  then 
is  caught  and  taken  back  to  the  feed  reel.  The  main  drive  handle 
may  have  a  shift  to  throw  it  to  a  rewind  position,  or  it  may  have  to 
be  removed  from  the  main  drive  shaft  and  placed  upon  the  end  of 
a  special  rewind  shaft;  in  either  case,  the  turning  of  the  handle  when 
changed  for  rewinding  will  turn  the  feed  reel  rapidly  and  will  wind 
the  film  back  from  the  take-up  to  the  feed  reel  and  at  a  much  faster 
speed  than  the  speed  of  projection — one  to  two  minutes  to  rewind 
a  reel  which  took  twenty  minutes  to  project. 

The  laws  of  New  York  and  possibly  of  some  other  states  do  not 
permit  the  rewinding  of  film  in  the  projecting  room.  It  must  be 
taken  from  the  projecting  machine  in  the  reel  and  rewound  to  a 
feed  reel.  Two  reels  mounted  edge  to  edge,  near  each  other,  with 
a  crank  and  gear  on  one  of  them,  is  the  rewinding  device  then  used. 

Automatic  Rewind.  Devices  for  avoiding  the  rewinding  of  the 
film  before  a  second  projection  have  been  suggested  and  tried. 
Fig.  34  shows  a  well-known  projector  equipped  with  the  automatic 
rewind,  or  rather  with  such  a  relation  of  take-up  and  feed  devices 
that  no  rewind  of  any  kind  is  recjuired.     The  feed  magazine  feeds 


1 
126  i 


.MOTION  HEAD 


53 


from  the  middle  of  the  roll  of  film  and  the  take-up  reel  rolls  the  film 
up  with  a  large  center  hole,  so  that  the  operator  may  take  the  roll 
of  film  from  the  take-up  magazine,  drop  it  into  the  feed  magazine, 
start  the  inner  end  through  the  film  outlet  and  thread  it  through  his 
motion  head  back  to  the  take-up,  and  his  machine  is  ready  for 
another  projection  of  the  film.  Not  only  does  this  sort  of  improve- 
ment save  the  operator's  time  and  labor,  but  it  saves  wear  on  the 
film,  which  becomes  scratched  in  rewinding  at  high  speed. 


■i 

^ 

s 

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9 

^ 

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Fig.  34.     Projector  with  Automatic  Rewind 

Another  type  of  machines  joins  the  leader  to  the  tail  of  the 
reel  and  runs  the  picture  twice  or  more  without  stopping,  if  desired. 

No  automatic  rewinds  are  in  general  use  in  theaters  as  yet, 
though  the  type  illustrated  in  Fig.  34  was  widely  sold  at  one  time, 
and  the  endless  belt  type  is  used  in  penny  arcades. 

Film  Basket,  or  Molasses  Can.  The  take-up  reel  goes  wrong 
in  operation  oftener  than  any  other  one  part  of  a  projector.  Often 
the  operator  must  stop  the  show  to  set  it  right,  and  in  the  middle 
of  a  picture  reel.  A  more  reliable  method  is  to  let  the  film  rim  from 
the  lower  steady  feed  into  a  sheet-iron  can  or  box  of  2  or  3  cubic 


127 


54  THE  MOTION  PICTURE 

feet,  folding  up  loosely  as  it  mns  in.  It  is  rewound  from  this  can 
to  the  feed  reel.  Because  of  the  early  practice  of  letting  the  film 
run  into  an  open  basket,  with  its  comparatively  great  fire  risk,  this 
take-up  can  is  still  called  a  "film  basket"  by  older  operators,  while 
it  is  called  a  "molasses  can"  also  from  the  manner  in  which  the  film 
folds  down  into  it.  AMiere  the  fire  ordinances  of  the  town  permit  it, 
the  can  will  be  found  to  "give  a  better  show"  than  the  take-up  reel; 
it  is  less  wearing  on  the  operator  and  on  the  film. 

Operator's  Control  of  the  Picture.  There  are  two  features  in 
which  the  operator  has  control  directly  for  modifying  the  picture — 
sfeed  of  projectioJi  and  brightness  of  light  o)i  the  screen.  Framing 
is  not  a  matter  of  arbitrary  control,  it  is  merely  a  necessary  detail 
which  must  be  kept  in  adjustment. 

The  picture  may  be  improved  by  reducing  flicker  when  possible 
by  reducing  the  illumination,  either  by  a  lamp  adjustment  if  con- 
venient, or  by  a  tinter;  preferably  the  tinter,  since  by  remwing  the 
tinter  the  full  illumination  is  restored  immediately  when  a  dense 
scene  is  projected  in  the  run  of  the  same  reel. 

Flicker  may  be  reduced  by  speeding  up  the  rate  of  turning,  also. 
In  the  case  of  a  picture  having  the  upper  part  of  the  screen  white 
sky  and  the  lower  part  dark  foreground,  the  illumination  must  be 
retained  to  make  the  foregroimd  visible,  and  the  only  means  for 
reducing  the  flicker  is  speed. 

The  sentiment  of  the  picture  may  be  watched  and  speed  may 
be  used  accordingly,  the  operator  turning  more  rapidly  where  he 
fleems  the  action  of  the  picture  could  l^e  improved  thereby.  The 
manufacturer  should  have  timed  his  action  when  making  the  picture, 
l)ut  sometimes  this  is  neglected. 

Motor  versus  Crank.  Most  cities  prohibit  the  motor  for  turning 
the  motion  head.  The  way  to  keep  the  operator  attending  closely 
to  his  film  is  to  keep  him  at  the  machine  turning  the  crank,  hence  all 
other  methods  of  driving  the  motion  head  are  forbidden,  ^^^lere 
the  motor  is  permitted,  a  small  electric  motor  of  the  usual  fan  size, 
tV  oJ"  tV  horse-power,  will  drive  it.  In  case  the  motor  is  used,  the 
film  always  should  be  started  and  turned  for  50  feet  or  more  with 
the  crank  before  the  motor  is  switched  on.  This  gives  the  operator 
the  "feel"  of  the  machine  and  tells  him  whether  everything  is  running 
as  it  should.     Then  the  labor  is  turned  over  to  the  motor  for  the 


128 


MOTION  HEAD  55 

greater  part  of  the  run  of  the  reel.  Just  before  tlie  end  of  the  reel  the 
operator  should  take  his  erank  again  and  shut  off  his  power,  again 
assuring  himself  by  half  a  minute  of  hand  turning  that  his  projector 
is  in  perfect  running  order  and  does  not  require  repairs  or  readjust- 
ment before  starting  the  next  reel.  The  operator's  hand  upon  the 
crank  is  the  doctor's  finger  on  the  pulse  of  the  patient;  the  slightest 
irregularities  in  mechanical  action  are  noted  by  the  "feel"  of  the 
handle.  The  operator's  eye  must  be  upon  the  screen  practically  all 
of  the  time  for  framing  and  focus,  even  if  not  for  flicker. 

FILM 

Films  of  all  makers  for  general  commercial  use  are  made  to 
about  the  same  size,  If  inches  wide,  ^i^o  i"<^'h  thick  including  celluloid 
and  gelatine;  of  this  width  of  If  inches,  a  strip  down  the  middle 
1  inch  wide  is  reserved  for  the  picture  and  the  holes  are  punched 
in  the  margins  near  this  strip,  ^\  of  an  inch  apart.  The  various 
makers  follow  this  standard  rather  loosely,  because  it  is  itself  rather 
loosely  composed  and  rather  indefinitely  expressed.  One  of  th(^ 
most  prominent  points  of  variation  is  the  shape  of  the  hole  used; 
another  is  the  distance  between  the  two  rows  of  holes,  or  the  distance 
from  either  edge  to  the  nearest  row  of  holes.  A  movement  is  being 
made  to  work  out  a  standard,  expressed  accurately  in  thousandths 
and  split  thousandths  of  an  inch.  It  is  believed  that  the  life  of  films 
will  be  lengthened  if  all  are  alike  and  the  projector  may  then  be  built 
accurately  to  that  film  size. 

Care  of  Film  in  Projecting.  Fit  the  film  accurately  to  the  sprockets 
before  starting  projection.  If  possible,  look  through  the  reel  for 
bad  edges,  bad  splices,  or  unframed  splices  before  beginning  pro- 
jection, and  repair  any  troubles  found.  Listen  to  the  purr  of  the 
film  over  the  steady  feed  sprockets  and  bad  places  in  the  sprocket 
holes  will  be  detected  when  running.  Watch  the  screen  for  unframed 
splices  and  for  focus;  a  film  which  rims  out  of  focus  for  a  few  seconds 
at  a  time  and  then  runs  true,  constantly  varying  the  focus  while  the 
lens  and  film  are  unmoved  and  the  film  gate  is  clean  and  perfect, 
may  be  warped;  it  shoukl  be  moistened,  as  discussed  under  the  sub- 
ject of  warped  films.  If  a  film  rattles  as  it  leaves  any_  of  the 
sprockets,  the  teeth  of  the  sprocket  may  be  worn  into  hooks;  a 
new  sprocket  is  the  proper  remedy. 


129 


56  THE  MOTION  PICTURE 

Care  of  Film  in  Rewinding.  Rewind  under  steady  tension.  Do 
not  rewind  loose  and  then  holding  the  film  take  up  the  slack  by 
winding  the  center  of  the  coil  tighter;  that  grinds  into  the  film  any 
grains  of  dust  which  may  have  been  collected  and  which  otherwise 
might  be  brushed  off.  In  rewinding,  the  film  may  pass  over  a  soft 
rag,  or  through  a  soft  rag  held  bunched  in  the  hand,  to  wipe  oft'  the 
dust,  the  first  time  it  is  rewound.  Particular  care  must  be  given 
to  the  gelatine  side  of  the  film  in  order  to  avoid  scratching. 

Care  of  Film  in  Storage.  The  film  should  always  be  packed  in 
metal  cans  or  flat  boxes  when  setting  it  away.  It  must  not  be  kept 
in  a  warm  place  as  the  celluloid  will  give  off  explosive  gases,  the 
gelatine  will  dry  out  and  warp  the  film,  and  the  celluloid  will  shrink 
with  the  heat,  particularly  if  it  be  an  XI  (non-inflammable)  film. 

Care  in  Handling  Film.  Do  not  let  the  ends  of  the  film  become 
unrolled;  they  are  liable  to  a  sharp  bend  which  leaves  a  crease  and 
ultimately  a  break.  Keep  the  roll  flat  when  off  the  reel.  The  dropping 
out  of  the  middle  in  a  cone  shape  and  pushing  back  again  only  adds 
scratches  where  none  are  needed.  Handle  by  grasping  the  flat  of 
the  reel  which  is  the  edge  of  the  film,  and  handle  as  little  as  possible. 

Packing  for  Shipment.  Place  the  film  first  in  the  iron  box,  then 
in  the  wood  box,  and  see  diat  the  danger  label  which  the  film  exchange 
puts  on  is  still  on  the  outside  of  the  box.  In  unpacking,  see  whether 
the  box  is  fastened  with  screws,  if  so  use  a  screwdriver,  not  a  hatchet; 
and  use  the  same  box  for  re-shipment  to  the  film  exchange. 

Repair  of  Films.  The  usual  method  of  repairing  films  is  to  cut 
out  the  defective  place  and  splice  the  ends  together,  thus  reducing  the 
length  of  the  film  by  the  few  small  pictures  cut  out  with  the  bad  place. 
Where  a  crack  is  seen  starting  across  the  film,  it  is  easier  to  take 
a  piece  of  clear  celluloid  film  strip  from  which  the  gelatine  has  been 
soaked  and  cement  h  inch  of  it  across  the  film  over  the  crack,  than 
it  is  to  splice  it.  This  is  cemented  upon  the  glossy  side,  leaving  the 
gelatine  and  the  picture  image  intact,  and  it  saves  the  order  of  pictures 
in  the  film  without  causing  a  sudden  jump  of  the  moving  characters 
when  the  fault  is  reached  in  projection.  The  film  thus  repaired  is 
no  thicker  than  a  splice,  and  will  pass  the  sprockets  and  film  gate 
with  the  same  ease.  The  patch  should  not  be  more  than  one-half 
a  j)icture  in  size,  or  the  film  will  be  stiffened  more  than  a  splice  would 
stiffen  it. 


130 


MOTION  HEAD 


57 


^Miere  the  sprocket  holes  have  a  bad  spot,  a  piece  of  blank 
film  (with  the  gelatine  soaked  off)  may  be  attached  sometimes  to 
avoid  cutting  out  good  images. 

Film  Splicing.  Cut  one  end  on  the  hne  between  pictures;  cut 
the  other  end  with  a  quarter  picture  on;  thus  in  cutting  a  film  there 
will  be  three-quarters  of  a  picture  cut  out,  a  picture  and  three-quarters, 
etc.    Moisten  the  gelatine  on  the  quarter  picture  and  scraoe  it  clean: 


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*■ — *— 

Fig.  35.     A  Splice  "In  Frame" 


Fig.  36.     A  Splice  "Out  of  Frame' 


also  scrape  the  celluloid  side  of  the  other  end  clean.  Spread  cement 
on  the  cleaned  quarter  picture  space  and  put  it  on  the  back  of  the 
other  end,  sticking  the  two  ends  together  with  the  picture  Hues 
matching  and  with  the  sprocket  holes  matching.  Cut  either  through 
a  sprocket  hole  or  midway  between  sprocket  holes,  straight  across 
the  film.    Small  scissors  are  more  convenient  than  a  knife. 


131 


58  THE  MOTION  PICTURE 

Splicing  hij  Machines.  A  number  of  forms  of  splicing  machines 
are  offered.  All  of  them  have  teeth  for  registering  the  sprocket  holes 
while  the  spHce  is  setting,  and  all  of  them  require  special  instruction 
and  some  skill  of  hand  and  common  sense.  Either  with  or  without 
the  machine,  get  some  scraps  and  practice  on  them  until  you  can 
make  it  right.  Your  film  exchange  or  a  friend  operator  will  give  you 
a  handful  of  short  pieces  for  practice;  and  the  cement  is  twenty-five 
cents  for  a  very  small  bottle.    A  fiat  stick  is  the  best  cement  spreader. 

Non-lnjiammahle  Film.  In  splicing  a  non-inflammable  film 
a  special  cement  is  required,  the  XI  film  cement  being  suitable  for 
either  ordinary  film  or  NI  film. 

Splicing  "in  Frame."  Splicing  a  film  "in  frame"  may  be  under- 
stood by  a  study  of  the  companion  figures.  Fig.  35,  which  shows  a 
splice  "in  frame"  and  Fig.  36  which  shows  a  splice  "out  of  frame." 

In  Fig.  35,  the  picture  C  has  four  holes  at  the  side,  just  as  have 
the  pictures  A,  B,  D,  E,  etc.,  and  when  that  film  is  passed  through 
the  film  gate  and  intermittent  mechanism,  the  "framing"  will  be 
preserved,  because  mechanically  the  film  is  the  same  in  distribution 
of  pictures  and  of  sprocket  holes  as  though  no  splice  had  been  made. 
The  difference  is  found  in  the  "jump"  of  the  pictures  where  a  picture 
or  more  have  been  omitted,  but  the  "frame"  will  not  be  disturbed  as 
the  splice  passes. 

In  Fig.  36,  the  picture  C  has  but  three  holes  at  the  side.  The 
result  is  that  when  the  picture  B  is  pulled  out  of  the  film  window  and 
the  picture  C  is  pulled  in,  the  intermittent  mechanism  pulling  down 
four  holes  will  pull  into  the  film  windoAV  the  three-cjuarter  picture  C 
and  also  the  top  quarter  of  the  whole  picture  D  •  Again,  upon  the 
next  operation  of  the  shift  mechanism,  the  intermittent  feed  pulls 
down  four  holes,  the  picture  C  will  be  pulled  down,  and  there  will 
be  jiulled  into  the  film  window  the  remaining  three-quarters  of  D 
and  the  top  quarter  of  E.  This  will  continue,  showing  the  lower 
three-fjuarters  of  one  picture  and  the  upper  quarter  of  another,  until 
the  (>j)erator  notices  the  screen  and  frames  with  his  lever.  This  is 
called  a  splice  "out  of  frame,"  because  the  splice  throws  the  picture 
out  of  frame  in  passing. 

Framing  hy  Splicing.  Every  time  a  splice  "out  of  frame"  is 
passed,  the  operator  must  "frame"  with  his  lever  until  he  can  find 
opportunity  to  stop  in  rewinding  and  cut  the  faulty  splice.    Then  he 


132 


MOTION  HEAD  59 

may  splice  it  correctly  "in  frame"  and  thus  put  his  reel  of  film  in 
frame  at  that  place  when  running. 

Titles.  Titles  should  be  given  the  same  care  as  the  picture  scenes 
of  the  film.  The  main  title,  forming  the  head  of  the  picture  film, 
should  be  given  the  favor  of  a  very  long  leader  if  the  title  itself  has 
been  shortened,  so  that  there  wall  be  ample  leader  to  thread  through 
to  the  take-up  reel,  to  turn  a  few  pictures  to  test  the  working  of  the 
take-up  before  closing  the  take-up  magazine  door,  and  further  to 
turn  a  few  pictures  and  get  the  motion  head  under  speed  })efore 
opening  the  fire  shutter.  Thus,  the  audience  will  get  the  full  benefit 
of  whatever  title  there  is. 

Leaders  and  Tails.  The  purpose  of  the  leader  and  tail  is  to  give 
the  audience  the  benefit  of  all  of  the  picture  which  lies  between. 
The  leader  is  a  piece  of  blank  film  or  a  piece  of  scrap  film,  just  so  it 
has  good  sprocket  holes,  cemented  to  the  title  end  of  the  reel,  and  of 
sufficient  length  to  thread  through  the  motion  head  and  test  the 
mechanism  before  bringing  the  title  into  the  film  window.  The  tail 
is  a  similar  piece  cemented  to  the  end  of  the  picture.  Its  purpose 
is  to  enable  the  operator  to  run  the  full  picture  on  the  screen  before 
closing  the  fire  shutter,  then  to  stop  his  motion  head  before  the  tail 
has  run  into  the  take-up  magazine  where  it  cannot  be  reached  con- 
veniently for  rewinding.  Some  motion  heads  are  so  constructed  for 
rewinding  that  if  sufficient  lengths  of  leader  and  tail  are  provided 
neither  end  of  the  film  need  be  detached  from  either  reel  if  but  one 
reel  is  to  be  run  repeatedly  in  the  projector.  Stopping  the  motion 
head  before  the  tail  has  been  drawn  from  the  spring  clip  of  the  feed 
reel,  the  film  is  rewound  and  the  rewinding  stopped  before  the  leader 
is  drawn  from  the  spring  clip  of  the  take-up  reel;  the  motion  head 
then  is  threaded  and  the  film  is  ready  to  repeat. 

Blank  black  film  mav  be  bought  from  the  film  exchange  for  leaders 
and  tails  if  the  reels  come  too  short  for  the  operator's  convenience. 

Dry  Film.  The  gelatine  of  the  motion  picture  strip  is  charged 
with  glycerine  by  the  manufacturer  in  order  to  keep  it  elastic  and 
to  make  the  film  pliable  in  handling  and  projecting.  As  the  glycerine 
and  the  water  which  is  held  in  the  gelatine  gradually  dries  out,  owing 
to  winding  and  rewinding  through  the  air  and  the  heat  of  the  arc 
lamp,  the  film  strip  becomes  dry  and  brittle,  with  a  tendency  to 
crack  the  gelatine  film,  which  then  tends  to  scale  off  from  the  celluloid. 


133 


GO  THE  :M0TI0N  PICTURE 

Films  may  be  moistened  and  their  pliability  restored  by  leaving  them 
unrolled  over  a  little  water,  not  permitting  the  water  to  touch  the 
film.  Take  a  bucket  holding  four  or  six  gallons,  cut  a  false  bottom 
of  heavy  wire  mesh  or  perforated  metal  with  legs  or  downturned 
edges  to  hold  it  1  inch  from  the  bottom  of  the  bucket.  Pour  in  \ 
inch  of  water,  set  the  false  bottom  in,  and  run  in  a  reel  of  film,  let- 
ting it  fold  around  as  film  does  in  a  basket  from  the  projecting 
machine.  Cover  the  bucket  for  half  an  hour.  ^Mien  the  film  is  reeled 
up  it  will  be  found  much  more  pliable. 

Warped  Film.  With  the  film  in  a  close  roll,  the  drying  from  the 
edges  goes  on  more  rapidly  than  from  the  central  portions  of  the  strip. 
This  warps  the  film,  making  it  take  a  cun-ed  section  crosswise  of 
the  film  when  it  should  lie  flat;  and  it  takes  the  cun-e  sometimes 
in  the  film  window,  putting  the  picture  out  of  focus  on  the  screen. 
Such  a  film  may  be  treated  with  the  vapor  bath  as  described  above, 
or  it  may  be  treated  more  simply  by  cutting  two  disks  of  thick  felt 
the  size  of  the  end  of  the  reel,  dampening  them,  putting  one  on  each 
side  of  the  reel,  wrapping  it  and  letting  it  lie  over  night.  Discretion 
must  be  used  to  avoid  getting  the  felt  or  blotting  paper  too  wet. 

OPERATOR'S  DUTIES 

Before  the  Show  Begins.  The  operator  usually  is  held  respon- 
sible for  delivery  to  the  tlieater  of  the  film  for  projection.  If  in  a  city 
where  the  film  exchange  is  visited,  the  operator  makes  the  visit, 
returning  the  old  reel  and  bringing  the  new  to  the  theater.  If  in  a 
town  distant  from  the  exchange,  he  is  responsible  for  the  packing 
and  shipment  of  the  old  reel  and  the  receipt  of  the  new  one  and  its 
delivery  from  the  express  office  to  the  theater.  Such  deliveries  may 
be  daily,  or  only  once  a  week. 

Being  thus  the  messenger  to  the  film  exchange  to  obtain  the 
picture  film,  he  is  also  made  responsible  for  getting  the  song  slides, 
and  not  only  the  slides  but  the  sheet  music  for  the  singer  which 
is  supposed  to  accompany  the  song  slides  but  sometimes  does  not 
except  after  a  special  effort  to  get  it.  If  tide  posters  are  used,  the 
operator  is  held  responsible  for  their  delivery  also,  as  being  some- 
thing substantially  a  part  of  the  film  reel.  Being  thus  in  charge 
of  the  signs  for  the  theater  front,  it  is  good  if  he  can  improvise 
signs  with  a  brush  and  a  sheet  of  paper  when   occasion   requires, 


134 


MOTION  HEAD  61 

or  when   the   title   poster   for  a  particular  reel  of   film    cannot  be 
obtained  as  usual. 

The  operator  is  responsible  for  keeping  up  the  necessary  supply 
stock  for  the  operating  room — carbons,  oil,  and  condensers  for  the 
lantern;  film  scrap  and  film  cement  for  repairing  films;  cover  glasses 
and  binding  strip  for  repairing  slides.  Whether  he  purchases  the 
supplies  himself  or  asks  the  manager  to  purchase  them  is  immaterial. 
If  the  supplies  run  short,  he  will  get  the  blame,  hence  the  burden  lies 
on  him  to  buy  or  keep  kicking. 

Preparing  for  Projection.  On  going  into  his  iron-bound  cage 
to  prepare  for  the  projection  of  films  and  lantern  slides  for  the  after- 
noon or  evening,  the  operator  should  turn  the  motion  head  at  a  good 
fast  rate  for  the  "feel"  of  the  machinery;  then  clean  the  film  gate, 
notice  the  gate  and  tension  plate  and  sprocket  teeth  or  intermittent 
pins  for  wear;  then  oil  up  ready  for  the  run;  clean  the  lamp,  dusting 
out  the  carbon  dust  which  collects  in  the  bottom  of  the  lamp  house 
from  the  sparks  thrown  off  from  the  arc;  examine  the  lamp  and  con- 
nections to  see  whether  any  wires  are  burning  weak  from  the  heat 
of  the  arc,  and  whether  any  joints  are  loose;  dust  the  table  top,  and 
lastly  sweep  off  the  lens  surfaces  with  the  camel's  hair  brush;  inspect 
the  carbon  stock,  and  if  insufficient  for  the  day  it  may  be  necessary 
to  omit  the  dissolving  lantern  or  to  set  the  rheostat  to  a  lower  notch 
to  save  carbon;  inspect  the  new  reel  of  film,  if  time  is  had,  strengthen- 
ing any  weak  spot  found  and  framing  up  the  reel  by  resplicing  "in 
frame"  any  splices  found  "out  of  frame";  trim  the  lamp  with  car- 
bons of  sufficient  length  for  the  first  reel,  light  up,  center  and  focus 
the  light,  put  in  a  slide  to  be  sure  that  the  stereo  lens  is  still  in  focus; 
then  put  a  piece  of  scratched  mica  (not  celluloid)  in  the  film  gate  for 
the  test  of  the  motion  head  lens  for  focus.  He  now  is  ready  to  begin 
projection. 

Conducting  the  Program.  The  duties  of  the  operator  after  the 
projection  begins  were  discussed  in  an  article  which  appeared  in 
the  N ickelodeou  and  which  seems  to  cover  the  subject.  It  reveals  the 
fact  that  the  operator  has  duties  other  than  turning  the  crank,  and 
that  training  in  actual  service  beyond  the  mere  mastering  of  the 
mechanism  of  some  particular  projecting  machine  is  an  essential 
to  the  person  who  would  become  an  efficient  operator  and  valuable 
theater  employe: 


135 


62  THE  MOTION  PirTl'RE 

Every  nickelodeon  has  its  stage  manager,  whether  it  knows  it  or  not. 

There  must  be  of  necessity  among  the  attendants  of  a  motion  picture 
theater  some  one  who  decides  when  the  pictures  shall  start,  when  the  song 
shall  be  sung,  and  how  long  the  intermissions  between  the  performances  shall 
be.  This  person  is  the  one  who  really  is  in  charge  of  the  program  of  the 
theater,  and  upon  him  depends  to  some  extent  both  the  pleasure  of  the  patrons 
and  the  profits  of  the  owner. 

In  a  small  theater,  running  to  one  reel  of  film  onlj^,  without  songs  or 
specialties  of  any  kind,  the  total  manual  duty  connected  with  this  duty  of 
controlling  the  program  is  the  turning  off  of  the  lights  in  the  room  when  the 
pictures  start,  and  turning  them  on  again  when  the  performance  is  finished. 
This  requires  merely  a  switch  in  the  operator's  booth,  convenient  to  his  hand, 
for  the  house  lighting  .system. 

In  such  an  instance,  the  operator  rewinds  the  reel  of  his  film  and  adjusts 
the  carbons  of  his  lamp.  He  is  ready  to  start  the  next  performance.  At  this 
point,  it  is  within  his  discretion  to  start  the  performance  immediately,  to  delay 
it  according  to  a  time  schedule,  or  to  delay  it  as  long  as  he  thinks  the  audience 
will  endure  the  wait  without  impatience.  It  can  be  seen  plainly  that  the 
pleasure  of  the  patrons  and  the  profits  of  the  owner  lie  within  control  of  the 
person  who  is  in  charge  of  the  program. 

As  the  theater  acquires  additional  features  of  entertainment  the  duties 
of  controlling  the  program  become  more  and  more  complex. 

By  adding  an  illustrated  song,  the  operation  of  the  projecting  machine 
becomes  more  complex.  In  addition,  the  operator  must  have  a  push  button 
to  call  the  singer  at  the  proper  time  to  be  in  readiness  when  the  song  slides 
come  upon  the  screen.  If  an  automatic  piano  or  phonograph  is  running  as 
a  barker  in  front  of  the  theater  and  is  making  so  much  noise  as  to  interfere 
with  the  enjoyment  of  the  song  (it  may  be  noted  that  patrons  sitting  in  the 
rear  of  the  room  will  be  much  nearer  to  the  automatic  barker  than  to  the 
singer),  then  the  automatic  barker  must  be  stopped  during  the  song,  requiring 
another  switch  to  be  controlled  by  the  operator. 

If  ventilating  fans  are  running  in  the  theater  during  the  pictures,  these 
in  all  probability  must  be  stopped  during  the  song,  since  the  whirring  of  the 
fans,  not  at  all  objectionable  during  the  pictures,  would  be  decidedly  so  during 
the  song.  With  an  illustrated  song  an  accompanist  is  required;  this  usually 
dispenses  with  the  expense  of  an  automatic  piano,  the  accompanist  playing 
during  the  intermissions.  The  operator  in  control  of  the  program  therefore 
is  required  to  call  the  accompanist  as  the  program  nears  the  close,  that  the 
intermission  music  may  start  promptly  at  the  close  of  the  pictures. 

What,  then,  are  the  total  duties  in  such  a  theater  which  are  required 
of  the  operator  usually  thought  of  as  only  a  picture-machine  operator? 

Take  the  easiest  form  of  .song-and-picture  program,  in  which  the  pictures 
follow  the  song. 

In  the  intermission,  the  pianist  is  on  duty.  The  operator,  having  his 
picture  film  in  readiness,  (1)  lights  his  arc  and  (2)  rings  for  the  singer.  He 
then  (3)  turns  out  the  lights  of  the  auditorium,  (4)  turns  off  the  ventilating 
fans,  (5)  turns  off  the  automatic  barker  and  (6)  projects  the  song  slides  in 
proper  order  and  at  the  proper  instant  for  each.  At  the  conclusion  of  the 
song,  he  (7)  shifts  to  the  motion  head  and  begins  to  turn  the  crank  of  the 


136 


MOTION  HEAD  63 

kinetoscope,  and  at  the  same  time,  with  his  free  hand,  (8)  he  turns  on  the 
ventilating  fans  and  (9)  turns  on  the  automatic  barker.  This  is  the  time  for 
the  accompanist's  period  of  rest,  and  as  the  operator  nears  the  end  of  the  reel 
he  (10)  rings  for  the  accompanist  to  be  in  readiness  for  the  intermission.  At 
the  end  of  the  motion  pictures  he  (11)  projects  the  Please  Remain  slide;  then 
(12)  turns  on  the  auditorium  lights,  (13)  cuts  off  the  current  from  his  arc  light, 
(14)  rewinds  the  film  and  (15)  adjusts  the  carbons  of  his  arc  lamp.  Last, 
but  by  no  means  least,  the  operator  (16)  decides  the  length  of  the  intermission 
before  repeating  his  routine  of  sixteen  separate  duties. 

With  every  added  feature  of  entertainment,  the  operator's  duties  become 
more   complex. 

An  alternative  plan  of  managing  the  performance  consists  of  placing 
a  stage  manager  at  the  theater  entrance,  inside  the  auditorium,  and  providing 
him  there  with  all  necessary  control  facilities.  An  array  of  electrical  switches 
control  the  barker,  the  house  lights  and  the  ventilating  fans;  push  buttons 
are  arranged  to  ring  buzzers  or  bells  in  the  operator's  booth  and  in  the  waiting 
room  of  the  performers  in  the  rear  of  the  picture  screen.  An  answering  buzzer 
circuit  may  run  from  the  waiting  rooms  to  the  stage  manager's  station,  or 
even  a  telephone  line  may  be  installed.  In  the  picture  machine  operator's 
booth  there  is  merely  one  switch  controlling  the  current  for  his  arc  lamp  and 
one  button' which  rings  a  buzzer  at  the  stage  manager's  station. 

This  system  operates  as  follows: 

When  the  machine  operator  is  in  readiness,  having  rewounel  his  films  and 
adjusted  his  lamp,  he  signals  to  the  stage  manager  by  pushing  his  button; 
then  he  merely  awaits  the  command  to  go  ahead  with  the  projection. 

When,  in  the  judgment  of  the  stage  manager,  the  performance  shall 
begin,  he  rings  for  the  singer  and  signals  the  operator  (two  buzzes  for  the 
song  slides)  and  when  the  first  slide  flashes  upon  the  screen  the  stage  manager 
cuts  off  the  house  lights  and  stops  the  barker  and  the  fans,  '\^'ith  applause 
after  the  song,  the  stage  manager  uses  his  discretion  as  to  whether  an  encore 
shall  be  sung,  and  either  rings  again  for  the  singer  and  signals  to  the  operator 
(three  buzzes  to  put  the  chorus  slide  back  on  the  screen)  or  rings  one  buzz  to 
the  picture  machine  operator  to  go  ahead  with  the  motion  picture  film  without 
encore;  at  the  same  time,  the  stage  manager  starts  the  fans  and  the  barker. 
As  the  pictures  near  the  close,  the  stage  manager  rings  for  the  pianist  and  then 
turns  on  the  house  lights  as  the  picture  closes.  He  then  must  wait  for  the 
buzz  from  the  operator  indicating  that  the  projecting  department  is  in  readi- 
ness again. 

^\  hen  vaudeville  or  specialties  of  any  kind  are  added  to  the  perform- 
ance, the  duties  of  the  stage  manager  become  more  complex,  and  the  machine 
operator,  whose  post  is  a  responsible  one,  should  be  relieved  of  them. 

Keeping  Up  With  the  Times.  The  live  projection  operator  who 
desires  not  only  to  give  a  good  show  and  hold  his  present  jol)  hut 
also  to  fit  himself  for  a  better  one,  must  keep  posted  upon  the  new 
ideas  that  are  being  developed  in  the  art  of  projecting  and  theater 
operating,  and  the  new  devices  which  are  being  produced  constantly 
by  enterprising  manufacturers.     Subscribe  for  some  motion  picture 


137 


64 


THE  MOTION  PICTURE 


magazine,  and  read  not  only  the  feature  articles  of  the  magazine, 
which  attract  attention  first  because  of  their  illustrations,  but  read 
the  editorials  and  the  advertisements.  Read  particularly,  and] 
with  care,  the  department  usually  entitled  "Manufacturer's  Depart-] 
ment"  or  "Notes  of  the  Trade,"  a  department  which  is  a  fusion  of] 
advertisement  and  editorial  and  which  supplements  both  the  adver- 
tising and  editorial  columns,  illustrating  and  commenting  upon] 
almost  every  new  thing  which  is  produced  in  the  motion  picture] 
business. 

Buy  the  new  books  of  the  art  as  they  are  brought  out  by  thej 
publishers;  read  them  and  understand  them  as  far  as  possible.  Talk] 
with  everybody  you  meet  in  the  picture  business  and  add  to  yourj 
own  knowledge  whatever  they  know.  Participate  in  the  "Questions"! 
columns  of  the  motion  picture  magazine  to  which  you  subscribe; 
either  with  questions  on  the  business  or  with  contributions  from  youi 
experience.  Be  alive,  whether  on  or  off  duty.  Then  when  some  good,! 
live  manager  needs  a  good,  live  operator  and  searches  his  memorjfl 
he  will  remember  YOU. 


138 


H 

a  '.2 

M  f  5 

H  :  fe; 


Hi 
p  o 


« 

H 


SCENE  FROM  PHOTOPLAY,  "THE  MINOR  CHORD' 

Courtesy  of  Independent  Mooing  Pictures  Co.,  Xew  York 


MOTION  HEAD 

PART  II 
SPECIFIC  PROJECTING  A\ACHINES 

Introduction.  The  progress  of  the  art  prevents  the  presenta- 
tion, in  any  one  book,  of  instructions  for  operating  all  and  every  one 
of  the  projection  machines  used  or  offered  for  sale.  A  new  detail 
is  added  to  some  standard  machine  every  month,  and  perhaps  an 
entirely  new  model  is  brought  out  by  an  old  and  well-estabhshed 
manufacturer,  or  a  new  manufacturer  springs  into  the  arena  to  fight 
for  a  part  of  the  motion-picture  trade  with  a  projecting  machine 
entirely  new  and  entirely  different  in  many  or  all  of  its  mechanical 
details.  To  keep  up  with  such  development  requires  at  least  a 
monthly  review  of  the  new  devices  and  improvements;  this  is  afforded 
ycu  by  the  trade  magazines. 

To  understand  the  current  news  of  improvements  and  to  be 
able  by  reason  of  that  understanding  to  operate  any  of  the  new 
devices  with  their  peculiarities  and  special  conveniences,  the  operator 
should  master  one  machine  thoroughly  and  learn  to  operate  it  per- 
fectly so  far  as  its  particular  mechanical  details  go.  Then,  or  be- 
fore then,  he  must  master  the  theory  of  each  operating  part  and 
regard  the  part  of  the  projector  which  effects  each  function  as  being 
a  little  integral  device  in  itself  which  may  be  replaced  with  an  im- 
proved device  designed  to  effect  the  same  function,  the  improved 
device  being  built  into  the  projector  without  changing  any  of  the 
other  details  of  the  machine. 

^Vhen  an  operator  has  attained,  a  skill  with  any  one  machine 
that  will  enable  him  to  operate  it  "with  his  eyes  shut  and  one  hand 
tied,"  and  when  he  has  added  to  this  physical  skill,  the  mental  mas- 
tery of  the  separate  results  to  be  accomplished  by  the  projector, 
and  has  learned  how  each  mechanical  detail  of  his  projector  is  specific 
to  one  of  these  separate  results,  then  it  is  a  matter  of  minutes,  not 
hours,  before  he  becomes  equally  skilled  with  any  machine  with 

Copyi-ight,  1911,  by  American  School  of  Correspondence. 


141 


66  THE  MOTION  PICTURE 

which  he  is  confronted  and  is  able  to  recognize  its  defects,  its  eccen- 
tricities, its  bad  adjustments,  and  its  worn  parts,  and  to  adjust  and 
replace  them  and  give  a  good  show  with  improved  projection. 

In  some  projectors,  the  feed  reel  magazine  is  square,  in  others 
it  is  round;  the  operator  who  has  skill  in  placing  a  full  reel  of  film  in 
a  square  magazine  cannot  fail  to  have  the  skill  to  place  it  in  a  round 
one,  nor  will  he  forget  to  close  and  latch  the  door,  nor  forget  to  feed 
the  end  of  the  film  down  through  the  film  outlet  before  closing  and 
latching  the  door.  In  every  other  detail  will  skill  in  the  operating 
of  one  machine  lead  to  the  operating  of  another. 

A  film  outlet  must  hold  a  film  close  while  passing  through; 
it  must  have  a  release  device  to  open  the  outlet  if  too  close  to  push 
the  end  of  the  film  through  easily.  The  Edison  outlet  has  but  one 
pair  of  rollers,  through  which  the  end  of  the  film  is  pushed  easily. 
The  Power's  Cameragraph  has  a  long  film  outlet  with  a  pair  of 
rollers  at  the  lower  end  where  the  film  cannot- be  pushed  through 
easily,  but  one  of  the  lower  rollers,  spring-pressed,  is  hung  with  its 
axle  through  slots  and  the  ends  of  the  axle  project  so  as  to  be 
caught  by  the  fingers,  whereby  the  spring  roller  may  be  drawTi  back 
to  open  the  outlet  and  let  the  end  of  the  film  freely  through.  The 
Edengraph  and  Motiograph  use  a  four-roller  trap  so  built  that  the 
rollers  at  one  end  are  opposite  a  slot,  and  the  end  of  the  film  niay 
be  carried  into  the  rollers  through  the  slot  of  the  outlet. 

Such  small  differences  in  mechanical  detail  will  be  all  that  is 
to  be  found  in  changing  from  one  projector  to  another.  Every  pro- 
jector has  its  feed  reel,  its  feed  reel  magazine,  its  feed  magazine 
film  outlet,  its  upper  steady  feed,  its  upper  feed  loop,  its  film  gate, 
its  intermittent  mechanism.,  its  take-up.  Every  lamp  has  its  four 
adjustments,  as  has  been  discussed  and  classified  heretofore,  and 
so  on  through  the  entire  list  of  necessary  functional  apparatus  units. 
Learn  one,  learn  it  well,  and  watch  for  the  differences  when  taking 
charge  of  a  strange  machine. 

In  ordering  repair  parts  for  any  projecting  machine,  give  as 
much  information  to  identify  the  machine  as  it  is  possible  to  give. 
To  write  to  the  Nicholas  Power  Company  asking  for  a  complete  new 
intermittent  mechanism  seems  hardly  sufficient  information.  It 
may  be  assumed  by  the  company  when  receiving  the  order  that  the 
mechanism  is  desired  for  a  Power's  Cameragraph,  but  the  inter- 


142 


MOTION  HEAD  67 

mittent  mechanism  for  the  No.  o.  Cameragraph  is  a  Geneva,  while 
the  intermittent  for  the  No.  6  Cameragraph  is  a  pin-cross  move- 
ment— and  which  one  do  you  need?  Some  manufacturers  change 
details  or  dimensions  of  parts  without  changing  the  number  of  the 
machine;  for  that  reason,  give  the  serial  number  if  it  can  be  found. 

The  serial  number  of  the  motion  head  is  a  number  stamped 
upon  the  frame  somewhere  with  numbering  punches,  just  as  a 
similar  number  is  placed  upon  watches,  bicycles,  and  pianos,  for 
identification. 

Write  in  this  manner:  "Please  send  me  for  Motiograph,  1010 
model,  serial  number  1263,  a  framing  device  connector  bar  167 
and  a  crank  handle  13^;"  The  numbers  of  the  parts  are  taken  from 
the  illustrated  lists  of  repairs,  if  possible  to  identify  them  in  the 
printed  lists;  if  not,  then  the  best  description  possible  must  be  given, 
or  if  convenient  to  do  so  the  worn  or  broken  part  may  be  sent  for 
identification  and  duplication.  Any  lack  of  care  in  ordering  is 
liable  to  produce  an  error  in  shipment,  or  to  produce  a  delay  by 
causing  the  dealer  to  write,  asking  for  further  information  in  order 
to  enable  him  to  fill  the  order. 

In  the  following  pages^  complete  instructions  are  given  for  a 
few  leading  machines,  not  only  for  operating  them  after  they  are 
set  up,  but  for  setting  them  up  for  beginning  service.  The  later 
paragraphs  will  not  repeat  instructions  where  they  are  similar  to 
those  already  given. 

THE  EDISON  KINETOSCOPB 

Installation.  First,  place  the  narrow  side  of  the  case  up;  re- 
move the  top  cover;  and  check  packing  slip. 

Remove  packages  in  main  compartment  as  follows:  adjustable 
legs,  rewind,  condensers  and  lenses,  cone  and  bracket,  switch,  cover 
and  cords,  lower  magazines,  lamp  house  with  arc  lamp,  crank  and 
lever  inside,  upper  magazine,  long  baseboard.  The  small  compart- 
ment contains  the  mechanism.  The  rheostat,  completing  the  out- 
fit, is  shipped  in  a  separate  box. 

Assembling.  Place  long  baseboard.  Figs.  37  and  38,  on  floor, 
bottom  side  up,  and  loosen  thumb  screws  on  flanges.  Extend  leg 
rods  in  all  tubes  and  insert  in  flanges,  fastening  l)y  means  of  leg 
clamp  screws,  adjusting  to  proper  height  by  clamp  screws  provided. 


143 


68 


THE  MOTION  PICTURE 


1  Carrying  case 

2  Base  board 

3  Base  board  wing  nuts 

4  Objective  lens  on  front  of  cabinet 

5  Lamp  house 

6  Lamp  house  casting 


INDEX  OF  PARTS 

23  Hand    wheel    for    lowering    and 

raising  lamp 

24  Carbon  feed  lever 

25  Lamp  body  lower  binding  post 

26  Switch  binding  posts 

27  Lamp  body  upper  binding  post 


Fig.  37.     Edison  Exhibition  Kinetoscope 


7-8 

Lamp  house  casting  guides 

28 

9 

Bolt  ajid  wing  nut 

29 

10 

Rear  slide  rod 

11 

Rear  slide  rod  set  screw 

30 

12 

Front  slide  rod 

31 

13 

Front  slide  rod  set  screw 

32 

14 

Condensing  lens  holder 

33 

15 

Condensing  lens  hood 

34 

16 

Mica  lid 

35 

17 

Slide  carrier  frame 

36 

18 

Condensing  lens  thumb  bolt 

37 

19 

Lamp  house  door 

38 

20 

Ruby  window  in  lamp  house  door 

39 

21 

Rear  door  of  lamp  house 

40 

22 

Hand   wheel   for   backward   and 

41 

forward  adjustment  of  lamp 

42 

To  rheostat  binding  posts 
Switch  binding  posts  for  the  main 

circuit  wires 
Film  aperture 
Stereopticon  support  rod 
Upper  reel 
Top  idler 
Top  sprocket 
Upper  spring  idler 
Film  gate 
LTpper  gate  idler 
Film  gate  tension  springs 
Lower  spring  idler 
Lower  sprocket 
Crank 
Framing  device  lever 


144 


I 


MOTION  HEAD 


69 


INDEX  OF  PARTS 

1  Mica  lid  6     Lump  house  door 

2  Condensing  lens  hood  7     Lamp  house  lid 


Fig.   38.     Edison  Kinetoscope,    Underwriters'  Model  Type  "B" 

3  Slide  carrier  frame  8     Hand    wheel    for    lowering    and 

4  Condensing  lens  holder  raising  lamp 

5  Ruby  window  in  lamp  house  door        9     Carbon  feed  lever 

/ 


145 


10 

Lamp  body  lower  binding  post 

22 

11 

Lamp  house 

23 

12 

Lamp  house  baseboard 

24 

13 

Lamp  house  baseboard  guides 

25 

14 

Swi^tch 

26 

15 

Condensing  lens  thumla  Ijolt 

27 

16 

Cone  holder  casting 

17 

SUde  carrier 

28 

IS 

Baseboard  chimp  casting  thumb 

bolt 

29 

19 

Framing  device  lever 

30 

20 

Top  sprocket 

31 

21 

Top  idler 

32 

70  THE  MOTION  PICTURE 

Upper  reel 

Film  gate 

Stereopticon  objective  lens 

Stereopticon  ring  casting 

Film  aperture 

Position  of  objective  lens  on  front 

of  mechanism 
Take-up      attachment      binding 

screws 
Crank 

Lower  sprocket 
Lower  spring  idler 
Rheostat 

Carefully  unpack  mechanism  and  remove  mechanism  cover 
by  loosening  thumb  screws.  Place  mechanism  on  baseboard,  secur- 
ing it  with  wing  nuts  screwed  in  baseboard. 

Assemble  lower  magazine  with  take-up  by  removing  wing  nut 
on  take-up  base  and  clamping  long  arm  over  shoulder  screws  on 
take-up  bracket  and  base.  Tighten  center  thumb  screw  directly 
under  mechanism,  then  place  long  bolt  over  take-up  sprocket  shaft 
pulley  passing  it  through  slot  in  baseboard,  then  around  small  pulley 
next  to  magazine,  over  large  pulley  on  take-up  reel  shaft,  and  under 
second  small  pulley.  Adjust  upper  magazine  and  bracket  to  mechan- 
ism support  by  means  of  the  thimib  screws  already  displaced  when 
mechanism  was  uncovered. 

One  film  reel  will  be  found  in  each  magazine. 
The  winding  crank,  adjusting  lever,  and  stereopticon  attach- 
ment which  will  be  found  inside  of  lamp  house,  may  now  be  attached 
to  the  mechanism  in  their  respective  places. 

Adjust  the  stereopticon  to  the  left  side  of  the  mechanism  sup- 
port by  the  thumb  screw,  washer,  and  wing  nut  provided. 

The  stereopticon  lens  and  lens  holder,  which  are  already  as- 
sembled, may  now  be  placed  on  the  stereopticon  slide  rod.  Screw 
motion  picture  lens  into  position  on  front  of  mechanism  support 
through  the  lens  ring  and  flange  already  attached  to  support. 

Lamp  House.  Loosen  the  two  small  set  screws  over  the  round 
opening  provided  for  slide  rods  in  lamp  house  bracket.  Place  the 
lamp  house  and  lamp  house  baseboard  on  this  bracket  with  that  side 
of  the  lamp  house  containing  a  large  round  opening,   toward   the 


146 


MOTION  HEAD  71 

mechanism.  Insert  the  two  shde  rods  through  round  openings  in 
bracket,  and  through  shde  castings,  being  sure  that  the  flanged  ends 
of  rods  are  on  the  stereopticon  side  of  the  lamp  house.  Tighten  the 
two  set  screws  in  lamp  house  bracket  above  referred  to,  to  hold  the 
rods  in  position.  These  rods  must  not  project  beyond  the  edge  of 
the  casting  where  they  are  fastened  with  the  set  screws.  Place  the 
rear  slide  or  door  of  lamp  house  in  position. 

Cone  and  Bracket.  Place  the  condensers  in  cone,  and  set  the 
same  in  position,  in  front  of  lamp  house,  fitting  it  in  the  round  open- 
ing of  lamp  house,  and  passing  the  cone  bracket  over  the  thumb 
screws  which  will  be  found  in  the  casting  attached  to  the  front  of  the 
lamp  house  baseboard,  then  tighten  the  thumb  screw.  When  plac- 
ing condensing  lenses  in  cone,  be  sure  that  the  side  of  the  condenser 
with  threaded  ring  will  be  in  position  next  to  the  arc  lamp.  Place 
slide  carrier  in  cone,  where  provided. 

Arc  Lamp.  This  will  be  found  packed  inside  the  lamp  house; 
remove,  clean  interior  of  lamp  house,  set  the  arc  lamp  in  lamp  base 
by  placing  the  stud  at  bottom  of  lamp  post  in  the  socket  in  center 
of  lamp  base,  then  tignten  round  head  screw,  so  that  the  lamp  may 
not  be  jarred  out  of  position,  when  operating.  Attach  ends  of  asbestos- 
covered  connecting  wires  by  removing  the  binding  post  thumb  screws 
on  upper  and  lower  carbon  holder  bases.  The  short  connecting  cord 
should  be  attached  to  the  lower  carbon  holder,  and  the  long  con- 
necting cord  to  the  upper  carbon  holder. 

Operation.  Carbons.  For  direct  current,  the  upper  carbon 
should  always  be  the  positive  pole,  while  the  lower  should  be  the 
negative  pole,  and  the  latter  set  ^  inch  in  advance  of  the  former  so 
that  a  crater  will  form  in  a  position  toward  the  condensers.  With 
carbons  of  the  same  diameter,  the  positive  burns  twice  as  rapidly 
as  the  negative,  thereby  requiring  more  or  less  adjusting  downward 
to  keep  the  crater  in  the  optical  axis,  for  this  reason  some  operators 
prefer  a  |-inch  soft  cored  upper,  or  positive,  carbon  and  a  ^inch 
hard  carbon  in  the  lower,  or  negative,  carbon  holder. 

This  difference  in  cross-section  compensates  in  the  matter  of 
lineal  consumption,  and  the  crater  is  kept  in  its  proper  place  with 
less  difficulty.  The  carbons,  when  burning,  should  be  kept  at  all 
times  as  near  to  Sg  inch  apart  as  possible.  -Most  satisfactory  results 
are  obtained  from  D.  C.  when  using  from  20  to  25  amperes. 


147 


72  THE  MOTION  PICTURE 

^Yhe^e  alternating  curroit  is  used,  the  carbons  should  be  set  in 
ahgnment,  although  some  operators  claim  to  get  better  results  by 
placing  the  lower  carbon  slightly  in  advance  of  the  upper.  This, 
however,  is  a  matter  of  choice,  and  the  careful  operator  will  usually 
experiment  in  the  adjustment  of  the  lower  carbon  until  he  gets  it  in 
a  position  most  satisfactory  to  himself. 

Both  carbons  should  be  soft  cored,  and  kept  as  nearly  as  possible 
to  ^  inch  apart.  They  are  consumed  at  about  the  same  rate,  the 
upper  carbon  about  8  per  cent  more  rapidly  than  the  lower,  owing 
to  the  upper  tendency  of  the  flame. 

The  most  satisfactory  results  are  obtained  on  alternating  cur- 
rent using  from  35  to  50  amperes. 

Fccusi}ig.  Adjust  the  lamp  house  by  means  of  sliding  base  on 
bracket  to  a  distance  of  16  inches  between  lamp  house  and  aperture 
or  picture  gate;  open  film  gate  on  mechanism,  and  proceed  to  regidate 
lamp  by  using  adjusting  handle  below  lamp  house  hinged  door.  Slide 
either  backward  or  forward  until  you  have  obtained  a  white  spot 
r|  inches  in  diameter  covering  the  opening  in  the  picture  gate.  For 
vertical  adjustment,  use  upright  adjusting  handle  on  the  arc  lamp 
post.  Adjust  the  projecting  lens  so  as  to  have  a  sharp  outline  of 
opening  in  picture  gate  on  the  screen. 

Stereopticon  Lens.  Slide  the  lamp  house  on  the  slide  rods  to 
the  flanged  ends.  Adjust  stereopticon  lens  in  front  of  the  condensed 
rays,  sliding  either  backward  or  forward  on  stereopticon  slide  rods, 
until  the  pi'oper  focus  is  obtained.  Adjusting  the  stereopticon  lens 
in  this  manner  permits  of  sliding  the  lamp  house  from  side  to  side,  alter- 
nating between  motion  picture  objective  lens,  and  stereopticon  lens 
as  desired,  without  rearranging  either  arc  lamp  position  or  lamp  house 
position. 

Connecting  Cords.  The  free  end  of  the  short  cord  to  be  attached 
to  a  contact  on  that  side  of  the  switch  where  no  open  poles  are  placed. 
The  free  end  of  the  long  connecting  cord  attached  to  the  upper  carbon 
holder  to  be  fastened  to  one  binding  post  in  rheostat  or  transformer. 
The  second  long  attaching  cord  to  be  placed  on  the  second  contact  of 
switch  where  no  pole  is  placed,  with  the  other  end  attached  to  the 
second  binding  post  in  rheostat  or  transformer. 

Take=up  Device.  The  take-up  device  comes  detached  from 
the  head  piece  mechanism,  and  is  adjusted  as  follows:     Insert   the 


148 


MOTION  HEAD 


73 


left-hand  part  of  the  take-up  device,  Fig.  39,  through  the  hole  in  the 

lower  part  of  the  cabinet.     The  hooks  3  on  the  frame  casting  of 

the  take-up  device  hang  on  the  half-inch  stud  in  the  lower  part  of  the 

head  piece  mechanism.     The  lugs  4  are  fastened  into  position  with 

two  8-32  machine  screws.     "\Mien  the  film  has  been  threaded,  as 

described,  and  fastened  to  the  spring  clip  of  the  core  of  the  take-up 

reel,  and  the  crank  handle  is  turned,  the  film  will  be  wound  on  the 

reel  as  fast  as  it  comes  through  the  machine.     If  the  reel  does  not 

revolve  fast  enough,  the  friction  adjusting  nut  5  should  be  screwed 

in,  thus  causing  the  friction  wheel 

6  to  engage  friction  disk  7,  causing 

the  reel  to  revolve  faster  and  take 

up  all  the  slack.      The  lever  S  is 

used  to  disengage  the  friction  wheel 

from  the  friction  disk  and  is  only 

used  when  the   film    is   rewound 

from  the  take-up  reel  to  the  top 

reel.    AMien  the  film  is  rewinding, 

this  lever  should  be  thrown  back 

toward   the   reel.       At    all   other  ng.  39.    Take-Up  Device 


INDEX  OF  PARTS 


1  Lower  sprocket 

2  Lower  idler  pulley 

3  Take-up  frame  hooks 

4  Take-up  frame  lugs 

5  Take-up  friction  adjusting  nut 


9 
10 


Take-up  friction  wheel 
Take-up  friction  disk 
Disengaging  lever 
Momentum  friction  spring 
Crown  gear 


times  the  Handle  of  the  lever  should  point  outward.  When  the  film 
is  rewinding,  use  the  friction  spring  9,  to  check  its  momentum  if  it 
turns  too  fast.  This  is  accomplished  by  pressing  down  the  spring 
until  the  end  rubs  against  the  inside  of  the  crown  gear  10.  This 
spring  is  only  used  when  the  film  is  rewinding.  At  all  other  times 
it  should  stand  in  position  as  indicated  on  Fig.  39. 

Wiring.  The  binding  post  10,  Fig.  40,  on  the  lamp  connects 
by  short  wire  with  switch  binding  post,  and  the  lamp  binding  post 
11  connects  by  long  wire  with  rheostat  binding  post. 

The  interior  of  the  lamp  house  is  planned  for  all  lights  known 
to  exliibitors,  including   the  electric  arc  light,  for  botli  alternating 


149 


74 


THE  MOTION  PICTURE 


and  direct  current,  tlie  oxy-hydrogen  (or  calcium)  burner,  the  Edison 
gaso-oxygen  burner,  or  the  methyl-etho  saturator.  Assuming  now 
that  we  are.  assembUng  the  electric  burner,  observe  the  following 
rules,  and  refer  to  Fig.  40.  The  lamp  base  1  is  assembled  ia  the 
lamp  house.  Place  lamp  post  S  in  socket  4  and  tighten  with  binding 
screw.  Next  place  carbon  in  carbon  holders  I4  and  tighten  car- 
bons with  thumb  screws  9.  .The  lamp  being  now  in  the  lamp 
house,  is  ready  to  receive  the  wires  12. 

The  main  line  should  be  wared  for  110 
volts  direct  current,  or  52  or  104  volts 
alternating  current,  25  to  40  amperes, 
using  a  standard  30-ampere  cut-out,  or 
combination  switch  and  fuse  block  with 
40-ampere  fuses.  If  alternating  current, 
60-ampere  fuse  may  be  used. 

\Mien    the    wires   12    are   connected, 

the    carbons    are    brought    together    by 

raising  the  feed  lever  8  to  make  the  arc. 

^'^"  Oxygeu  Ligu'*'    ^^°'        After  closiug  the  circuit  through  the  car- 


INDEX  OF  PARTS 


J 

Arc  lamp  base 

9 

2 

Hand    wheel    for    forward 

and 

10 

backward  adjustment 

11 

3 

Lamp  post 

12 

4 

Lamp  post  base  socket 

13 

5 

Hand    wlieel    for    lowering 

and 

raising 

14 

6 

Lamp  post  friction  screw 

A. 

7 

Lamp  body 

D. 

8 

Carbon  feed  lever 

Carbon  holder  thumb  screws 
Lamp  body  lower  binding  post 
Lamp  body  upper  binding  post 
Wires 

Raising  and  lowering  lever  fric- 
tion screw 
Carbon  holders 
Socket  for  alternating  current 
Socket  for  direct  cvuTent 


bons,  they  should  be  separated  about  \  inch  to  make  a  perfect  arc. 
This  is  done  by  lowering  the  feed  lever  slightly.  A  perfect  circle  of 
white  light  should  cover  the  aperture  30,  Figs.  37  or  38.  All  this 
is  done  before  the  film  is  threaded  into  the  mechanism.  Should  the 
circle  of  light  on  the  aperture  be  imperfect,  it  may  be  remedied  by 
either  or  all  of  the  following  adjustments: 


150 


MOTION  HEAD  -  75 

By  swinging  the  lamp  either  to  the  left  or  right  (revolving  on  the 
lamp  pest),  using  the  hand  wheel  ^,  J'ig.  40,  as  a  lever;  or  hy  raising 
or  lowering  the  lamp  by  turning  hand  wheel  5,  or  by  a  forward  and 
back  adjustment  by  hand  wheel  2.  The  size  of  the  circle  light  cover- 
ing the  aperture  can  be  increased  or  diminished  by  sliding  the  lamp 
backward  or  forward. 

If  a  "ghost,"  or  dark  spot,  appears  in  the  middle  of  the  screen, 
this  can  be  remedied  by  sliding  the  entire  lamp  house  backward  or 
forward  on  the  large  baseboard. 

The  set  screw  and  tension  device  6  is  placed  on  the  lamp  for  the 
purpose  of  giving  an  amount  of  friction  necessary  to  prevent  the  lamp 
from  dropping  on  the  post  from  its  own  weight.  This  set  screw  should 
be  snugly  tight,  but  not  tight  enough  to  bind.  The  set  screw  13  is 
for  tightening  the  friction  bushing  on  shaft  of  handle  5.  This  also 
prevents  the  lamp  from  dropping  from  its  owti  weight.  This,  how- 
ever, should  not  be  too  tight. 

Six  Edison  Rules.  First.  Adjust  the  height  by  raising  or  lower- 
ing the  lamp  on  the  lamp  post  3  by  the  hand  wheel  5,  Fig.  40,  until 
the  points  of  the  carbons,  when  brought  together,  are  opposite  the 
center  of  the  condensing  lens. 

Second.  Turn  on  the  current  by  closing  knife  switch.  Lift  up 
mica  lid  16,  Fig.  37.  The  revolving  mica  shutter  behind  the  fram- 
ing plate  should  be  turned  so  as  to  leave  the  space  between  the  fram- 
ing plate  and  the  objective  lens  entirely  clear.  This  should  be  done 
before  the  film  is  placed  in  the  machine. 

Th  ird.  The  lamp  should  then  1  )e  adjusted  by  moving  backward 
or  forward  until  a  bright,  clear,  round  light  just  covers  the  s(|uare 
hole  in  the  framing  plate.  If  the  circle  of  light  is  too  large,  light  is 
lost  and  the  brightness  of  the  picture  is  impaired.  ^Mien  properly 
adjusted,  the  light  on  the  screen  will  be  bright  and  free  from  color. 

Fourth.  The  operator  should  adjust  the  objective  lens  by  turn- 
ing the  focusing  screw,  until  the  square  on  the  screen  is  sharply  de- 
fined. Only  a  slight  adjustment  is  then  required  to  sharpen  the  pic- 
ture when  projected. 

Fifth.     All  this  should  be  done  before  the  film  is  threaded  up. 

Sixth.  Never  turn  the  light  on  the  film  until  it  is  in  motion, 
and  if  by  accident  or  mistake  the  film  should  stop  while  the  light 
is  on,  shut  mica  lid  16,  Fig.  37,  at  once,  or  the  film  will  catch  fire. 


151 


76  •       THE  MOTION  PICTURE 

Calcium  or  Qaso=Oxygen  Light.  \Mien  calcium  or  gaso-oxygen 
light  is  used  by  tlie  operator,  tlie  arc  lamp  base  1,  Fig.  40,  remains 
in  position  on  the  floor  of  the  lamp  house.  Into  the  socket^  is  inserted 
the  eccentric  holder  post,  with  which  every  complete  projecting 
kinetoscope  is  equipped.  The  post  must  not  be  clamped  too  tightly; 
it  must  be  loose  enough  to  permit  the  eccentric  holder  to  move  to 
right  or  left  and  forward  or  back,  as  may  be  necessary  in  centering 
the  light  on  the  condenser.  The  clamp  screw  may  be  tightened  after 
the  center  is  found. 

Directions  for  Operaiing.  Remove  jet  from  lantern  to  place 
lime  pencil  in  straight  position  into  lime  cup  "within  \  inch  from  point 
of  jet. 

Turn  on  the  hydrogen  gas  (black  cylinder)  first  until  the  flame 
becomes  the  size  of  a  light  from  an  ordinary  gas  burner.  Then  turn 
the  oxygen  gas  (red  cylinder)  slowly  until  the  light  gets  bright  and 
dazzling.  Too  much  oxygen  dulls  the  light  and  may  extinguish  it; 
yellowish  flames  of  hydrogen  should  always  be  noticed  around  the 
lime  pencil.  If  not  intense  enough,  add  small  portions  of  the  gases 
initil  the  light  is  nearly  hissing.  Turn  off  oxygen  first  and  then 
hydrogen. 

Tuni  lime  pencil  about  every  few  minutes,  to  prevent  cracking 
of  condensers  and  see  that  no  draft  strikes  the  lanterii. 

If  light  snaps  out,  shut  off  both  gases  and  re-light  as  above 
stated. 

Observe  rules  3,  4,  5,  and  6  above. 

The  gaso-oxygen  saturator  and  burner  are  especially  adapted 
for  traveling  exhibition  purposes,  and  also  for  home  use.  A  com- 
plete description  of  the  gaso-oxygen  outfit,  together  with  directions 
for  generating  the  gas  and  adjusting  the  burner,  will  be  found  under 
the  heading  "Directions  for  Operating  the  Gaso-Oxygen  Light." 
Rules  3,  4,  5  and  6,  above,  must  be  carefully  observed. 

Threading  up  the  Film.  The  film  is  wound  on  the  upper  reel 
32,  Fig.  37,  by  placing  the  end  in  the  spring  clip  on  the  core  of  the 
reel.  The  emulsion  side,  that  is,  the  gelatine  side,  should  be  in. 
\Mien  the  reel  is  full,  the  end  of  the  film  is  brought  under  the  lower 
front  side  of  the  reel.  It  passes  over  top  idler  33,  under  top  sprocket 
34,  over  the  upper  spring  idler  35.    Now  open  film  gate  3G. 

Engage  the  film   on   the  intermittent  or  mitldle  sprocket  (not 


152 


MOTION  HEAD  77 

shown  in  cut),  leaving  about  3V  inches  of  the  fihn  slack.  The  gate 
is  then  closed  and  secured  by  latch,  thus  forcing  the  slack  film  into 
a  loop,  the  lower  part  of  which  passes  behind  the  upper  gate  idler 
37,  as  shown.  The  film  is  now  between  the  framing  plate  and  the 
film  gate  36.  As  it  passes  the  aperture  30  the  film  is  held  against 
the  framing  plate  by  the  springs  38.  This  checks  the  momentum 
of  the  film  and  prevents  the  center  of  film  from  touching  the  gate, 
thus  avoiding  possibility  of  scratching. 

A  second  loop  is  then  formed.  This  is  kno^^^l  as  the  lower  loop 
and  should  be  about  2  inches  in  length.  This  is  formed  by  passing 
the  film  under  the  lower  take-up  sprocket  and  over  the  grooved 
idler  spring  pulley,  which  is  closed  against  the  film  to  hold  it  firmly 
against  the  lower  sprocket.  Having  then  formed  both  loops,  and  the 
picture  sitting  squarely  between  the  tension  springs  38  and  grooved 
framing  plate,  the  film  is  next  passed  over  the  hard  rubber  roller, 
which  will  be  found  immediately  in  front  of  the  lower  take-up  sprocket. 
The  end  of  film  is  then  passed  under  the  core  of  the  take-up  reel 
and  secured  by  the  steel  clip  on  the  core.  The  machine  is  then  ready 
to  be  set  in  motion,  which  is  done  by  turning  the  crank  4^  away 
from  the  operator.  The  framing  lever  4-  should  be  adjusted  with  set 
screws  bearing  on  the  flat  surfaces  of  the  lever.  The  picture  is  then 
framed  upon  the  screen  by  lowering  or  raising  the  lever. 

The  emulsion  side  of  the  film  should  be  always  toward  the  light 
and  the  picture  should  show  in  the  aperture  upside  down. 

Framing  Device.  As  has  been  noted  there  is  no  setting  or  adjust- 
ing of  the  film  as  it  passes  o^•er  the  frame  plate.  This  is  rendered 
unnecessary  by  the  framing  device.  After  the  picture  appears  on 
the  screen,  if  it  is  not  framed  exactly,  it  is  very  easily  accomplished 
by  raising  or  lowering  the  lever  4^  until  the  proper  effect  is  obtained. 

Adjustable  Rheostat.  After  the  rheostat  is  placed  in  circuit 
as  described  under  the  heading  "AViring,"  the  current  may  be  regu- 
lated by  raising  or  lowering  the  contact  spring.  Before  turning  on 
light,  the  contact  spring  should  be  set  at  the  bottom  of  the  rheostat 
so  as  to  prevent  too  much  current  being  drawn  suddenly,  and  burn- 
ing out  fuses.  If,  after  lighting  the  lamp,  the  light  is  not  strong 
enough,  raise  the  contact  spring  until  the  desired  strength  is  obtained. 

General  Instructions.  The  intermittent  sprocket  shaft  is  pro- 
vided with  bronze  eccentric  bushings,  and  set  screws  are  placed  in 


153 


78 


THE  MOTION  PICTURE 


the  cast  frame  to  hold  these  bushings  secure.  The  idea  of  making 
the  bushings  eccentric  is  to  permit  the  operator  to  adjust  them  so  that 
the  star  wheel  and  cam  fit  perfectly,  thus  avoiding  unsteady  pictures. 
If  vou  wish  to  show  steady  pictures  upon  the  screen  at  all  times,  it 
is  necessary  to  look  carefully  to  the  adjustment  of  these  eccentric 
bushings,  and  when  these  eccentric  bushings,  or  the  star  wheel  or 
cam,  or  the  intermittent  sprocket  become  worn,  it  is  highly  essential 
to  good  results  that  they  be  replaced  at  once.  See  that  all  set  screws 
are  kept  tight,  and  the  machine  well  oiled,  so  that  it  A\ill  run  smoothly 

and  regularly  at  all  times.  Be  care- 
ful not  to  use  too  much  oil,  as  surplus 
oil  is  liable  to  spatter  on  the  film  and 
damage  it. 

Films  should  be  handled  carefully 
and  kept  clean  and  free  from  dust. 

They  should  be  wound  on  reels 
when  not  in  use,  and  placed  in  a 
dust-proof  reel  box,  and  if  possible 
kept  in  a  cool,  dry  place. 

The  films  should  be  kept  in  perfect 
condition,  any  broken  places  being 
mended  at  once. 

Film  Winder.     This  ingenious  little 
apparatus,  Fig.  41,  is  a  great  labor- 
saver.     It  is  small  and  compact  and 
can  be  placed  on  any  table  or  shelf 
that    may    be    near    the    projecting 
machine,  being  provided  with  thumb  screws  for  instantly  adjusting 
it  to  a  table.     If  a  Kinetoscope  is  not  equipped  with  a  take-up  reel, 
this  film  winder  is  an  absolute  necessity. 

After  the  film  has  been  run  through  the  projecting  macliine  the 
end  is  placed  in  the  groove  of  the  winding  shaft  with  the  emulsion 
side  in;  and  by  turning  the  crank  of  the  winder  slowly,  a  100-foot 
film  can  be  properly  wound  in  less  than  ten  seconds  of  time.  There 
is  an  attachment  on  the  winder  for  removing  the  film  from  the  shaft 
after  it  has  been  wound,  in  perfect  safety  and  in  a  perfect  roll. 

This  attachment  consists  of  a  nickel-plated  disk  of  about  the 
diameter  of  a  l')0-foot  film  when  rolled  up.     This  disk  slides  from 


Fig.  41.     Film  Winder 


154 


MOTION  HEAD  79 

front  to  back  of  the  shaft.  After  the  film  is  wound,  the  exhibitor 
sHdes  the  disk  from  back  to  front  carrying  the  roll  of  film  with  it,  thus 
freeing  it  from  the  shaft. 

Edison  Film  Mender.  First  open  all  gates.  Place  one  end  of  the 
film  on  left-hand  side  of  repairer,  emulsion  side  up,  with  the  bottom 
line  of  picture  as  near  the  center  of  the  glass  as  possible,  then  close 
and  clamp  left-hand  gate  over  the  film.  Place  the  widest  part  of  the 
gauge,  which  forms  part  of  the  repairing  outfit,  against  the  closed 
gate,  and,  holding  it  firmly  on  the  film,  take  a  sharp  knife  and  cut 
off  that  portion  of  the  film  which  projects  beyond  the  gauge. 

Next,  reverse  the  gauge,  place  it  with  the  narrowest  part  over  the 
film  and  close  against  the  locked  gate,  moistening  that  portion  of 
the  film  which  projects  beyond  the  gauge,  and  sci^ape  off  the  emul- 
sion. For  this  use  a  moderately  sharp  knife.  Be  careful  not  to 
scratch  away  the  celluloid.  After  this  is  done,  open  the  gate  and 
move  back  the  film  so  that  it  will  be  entirely  covered  by  the  gate, 
and  re-lock  the  gate. 

Next  take  the  other  end  of  the  film,  place  it  on  the  right-hand 
end  of  the  repairer  in  the  same  manner  as  was  done  before,  with 
the  picture  line  as  near  the  center  of  the  glass  as  possible.  Use  the 
gauge  in  the  same  manner  as  before,  that  is,  use  the  widest  side 
and  cut  off  that  portion  of  the  film  which  projects.  This  end  of 
the  film  should  not  be  moistened,  nor  shoidd  the  emulsion  be 
scraped  away. 

After  this  is  done,  release  the  left-hand  gate  and  place  that  end 
of  the  film  in  the  same  position  as  it  was  after  the  first  operation  had 
been  performed.  You  will  then  note  that  the  ends  will  overlap  about 
^  of  an  inch.  Moisten  both  ends  of  the  film  with  the  film  cement 
where  they  overlap,  cement  the  two  ends  together  carefully  and 
smoothly  (the  one  with  the  emulsion  scraped  off  underneath),  close 
dowTi  the  center  door  or  gate  and  lock  same  securely.  Leave  the 
film  in  this  position  for  from  20  to  30  seconds,  when  same  will  be 
thoroughly  cemented  together. 

\Mien  about  to  take  the  film  from  the  repairer,  open  the  center 
gate  first  and  if  the  film  is  found  to  adhere  to  same,  by  working 
same  carefully  to  the  right  and  left  the  film  will  be  released  from  the 
gate  without  breaking  the  joint. 

Operating  Qaso=Oxygen   Light.    The   gaso-oxygen  light   is   the 


155 


80 


THE  MOTION  PICTURE 


result  of  a  series  of  exliaustive  experiments,  and  it  is  offered  fre- 
quently as  a  substitute  for  the  methjl-etho  light  outfit,  for  the  reason 
that  it  is  strong,  simple,  and  cheap  to  operate.  The  operation  of 
the  light  is  very  simple,  and  in  order  to  make  it  perfectly  clear,  the 
directions  are  given  under  three  different  headings,  as  follows:  (1) 
the  chemicals;  (2)  the  oxygen  generator;  (3)  the  gaso-oxygen  satura- 
tor  and  burner. 

Necessary  Chemicals.  The  necessary  chemicals  can  be  obtained 
in  almost  any  large  town  if  the  original  supply  becomes  ex- 
hausted. Buy  the  chemicals  from  a  reliable  druggist,  and  see 
that  there  are  no  chips  or  other  combustibles  mixed  with  the  chlorate 
of  potash  or  the  black  manganese.  The  following  chemicals  will 
suffice  for  two  hours  continuous  running:  2  lbs.  chlorate  of  potash, 
and  ^  lb.  black  manganese  (in  the  retort  1,  Fig.  42),  \\  pints  90  deg. 
gasoline  (in  the  saturator),  and  1  Hme  pencil. 

Mix  4  parts  of  chlorate  of  potash  and  1  part  of  black  manganese 
thoroughly  and  distribute  it  equally  along  the  entire  length  of  the 
retort  1 .     Turn  the  retort  so  that  the  seam  comes  on  top. 


FOR  GENERATING  OXYGEN  GAS  INTO  GAS  BAG  ONLY 


1  1  Russia  iron  retort  and  cleaner 

3i  X18 

2  1  Retort  stand 

3  1  Burner  (gas  or  spirit) 

4  16-inch  lined  tubing  from  retort 

to  purifier 

5  2  Purifiers,  complete  with  rubljer 


stoppers,  glass  and  metal  tubes 
6-ft.  rubber  tubing  |  X  3-16  con- 
necting purifiers  to  gas  bag 
1  55-gal.  gas  bag,  stopcocks  and 

regulator 
5-ft.  rubber  tubing  i  Xi  from  gas 
bag  to  light 


FOR  GENERATING  AND  COMPRESSING  OXYGEN  GAS 


1  1  Russia  iron  retort  and  cleaner,         7 

3^X18 

2  1  Retort  stand  8 

3  1  Burner  (gas  or  spirit) 

4  16-inch  lined  tubing  from  retort        9 

to  purifier  10 

D     2  Purifiers  complete,  with  rubber 

stoppers,  glass  and  metal  tubes      1 1 
G     6-ft.  rubber  tubing  |X3-16  con- 
necting purifiers  and  gas  bag  12 


1  55-gal.    gas    bag    and    double 

stopcock. 
5-ft.  rubber  tubing  |  X3-16  from 

gas  bag  to  pump. 
1  Compressor 
5-ft.  lined  tubing  and  couplings 

from  compressor  to  cylinder 
1    gauge   attachment,    regulator 

and  5-ft.  tubing  to  light 
1  25-ft.  cylinder  and  key 


156 


MOTION  HEAD 


81 


Fill  the  retort  1  as  above.  Connect  the  purifiers  5  as  shown  in 
Fig.  42.  The  purifiers  should  be  half  filled  with  pure  water  and  \ 
ounce  of  caustic  soda  placed  in  bottle  nearest  the  retort.  Be 
careful  that  the  ends  of  tubes  AA  are  helow  the  surface  of  the  water 
and  the  ends  of  tubes  BB,  above  the  water. 

The  gas  bag  7  should  be  rolled  before  connecting,  to  eject  all 
air.  Place  the  burner  3  on  retort  stand  2  at  one  end  of  the  retort  1. 
Gas  will  generate  as  soon  as  heat  is  applied.  Allow  a  little  oxygen 
to  be  given  off,  before  finally  connecting  the  retort  1  with  the  tubing 
4  to  the  first  purifier  5.     To  ascertain  when  the  gas  is  pure,  light 


Fig.  42.     Oxygen  Generator 

a  piece  of  bro^vn  paper,  thoi  blow  it  out,  and  hold  the  smoldering 
portion  in  front  of  the  arm  of  the  retort  1.  AMien  the  gas  is  pure, 
the  paper  will  burst  into  flame;  then  connect  with  tube  4  ^-^id  see 
that  all  the  tubes  are  straight.  Now  open  the  tap  of  the  gas  bag  7. 
Scores  of  people  forget  to  do  this.  The  gas  bag  7  is  now  filling 
with  pure  oxygen  gas.  INIove  the  burner  3  along  under  the  retort 
1  inch  by  inch  until  the  chemicals  are  exliausted.  As  soon  as  the  bag 
is  quite  full,  turn  off  the  tap  at  gas  bag,  remove  the  burner  from  the 
retort,  and  disconnect  the  tubing. 

AMien  using  the  gas  bag  a  pressure  of  150  to  200  pounds  is  re- 
quired to  procure  the  best  results,  which  is  obtained  by  means  of  press 
boards  and  weights.  The  capacity  of  the  gas  bag  is  55  gallons,  and 
about  2  pounds  of  chemicals  must  be  used  to  fill  it  completely. 

The  gas  bag  should  be  kept  in  a  warm  place  when  not  in  use. 


157 


S2 


THE  MOTION  PICTURE 


Wash  out  the  retort  with  hot  water  as  soon  as  possible,  and  do  not 
attempt  to  pick  out  the  baked  residue  with  a  chisel  or  other  sharp 
instrument,  as  this  spoils  the  retort.  Don't  leave  mixture  to  harden ; 
unless  the  retort  is  cleaned  at  once,  it  is  almost  impossible  to  remove 
the  hardened  residue. 

^^^len  the  high-pressure  method  is  used,  the  oxygen  gas  is  com- 
pressed into  cylinder  12  with  the  compressor  9  until  about  100 
pounds  pressure  is  reached  in  cylinder  12. 

Gaso=Oxygen  Saturator  and  Burner,  The  gauge  attachment, 
Fig.  43,  is  supplied  with  two  needle  valves;  turn  on  first  the  one  lead- 
ing to  the  saturator,  see  that  valves  C  and  D  are  also  open,  and 
light  the  jet,  then  turn  on  the  oxygen  from  valve  B,  and  regulate 
your  light  in   the  same  manner  as  oxy-hydrogen  gas  is  used,  until 


Kig.  43.     Gaso-Oxygen  Saturator  and  Burner 

the  light  is  bright  and  dazzling.  Too  much  oxygen  dulls  the  light, 
and  may  extinguish  it.  Little  red  flames  should  always  be  noticed 
around  the  light,  to  show  that  sufl^cient  gasoline  or  ether  is  supplied. 
If  the  light  is  not  intense  enough,  add  small  portions  of  the  gases 
until  the  light  is  nearly  hissing. 

Always  turn  on  the  gasoline  first  when  lighting,  and  when 
through,  turn  off  the  oxygen  first.  Have  the  lime  pencil  properly 
adjusted  about  f  inch  above  the  point  of  the  jet  when  starting, 
and  turn  the  pencil  upward  about  every  five  minutes,  to  prevent 
the  flame  from  burning  through  the  pencil  and  striking  back  against 
the  condenser,  as  this  will  crack  it.  See  that  no  draft  strikes  the 
lantern,  thereby  causing  the  condenser  to  break. 

Should  the  light  snap  out,  it  is  a  sign  that  too  much  oxygen  is  used, 
then  both  gases  must  be  turned  off,  and  relighted  as  above  directed. 


158 


MOTION  HEAD 


83 


Fig.  44.     Automatic  Shuttet 

for  Underwriters'  Model  of 

Edison  Kinetoscope 


It  is  imperative  that  90-degree  gasoline  only  is  used,  as  lower 
grades  will  not  evaporate  quickly  enough  to  give  sufficient  supply 
of  lighting  material. 

In  changing  the  fluid  from  gasoline  to 
ether,  it  is  necessary  to  open  the  saturator, 
take  out  the  cotton,  and  have  it  thoroughly 
cleaned,  by  exposing  it  to  the  air  until  it  is 
perfectly  dry. 

Note  the  following  differences  over  the 
other  saturators: 

Ninety-degree  Gasoline  or  Sulphuric  Ether 
can  be  used  with  utmost  and  absolute  safetj',  as 
there  is  no  direct  connection  between  fluid  and 
flame  and  consequentlj^  no  danger.  Any  number 
of  lights  can  be  run  from  one  saturator,  and  any 
single  or  dissolving  lantern  jet,  or  dissolving  key 
can  be  adapted. 

The  1,000  candle-power  jets  give  the  same 
light  with  gasoline  saturator,  as  with  oxy-hj'drogen 
gases. 

The  saturator  is  equipped  with  needle  valves  and  regulators,  guaranteed 
air  tight. 

If  no  cylinder  is  used,  and  the  oxygen  gas  is  supplied  direct  from  the  gas 
bag,  it  is  necessary  to  use  a  stand  with  two-way  connections  near  the  saturator 
to  regulate  the  gases  conveniently,  in  the  same  manner  as  above  described. 

Automatic  Shutter.  On  Under- 
writers' Model.  Under  no  possible  condi- 
tions can  the  light  be  thrown  upon  the 
film  except  when  the  film  is  in  motion. 
Wlien  the  shutter,  Fig.  44,  is  wide  open 
it  automatically  locks  so  that  no  power 
is  required  to  keep  it  open,  eliminating 
undue  wear  on  the  gearing  and  causing 
easier  operation  of  mechanism.  \Mien 
the  speed  of  the  machine  falls  below  a 
certain  point,  however,  it  automatically 
unlocks  and  closes. 

On  Exhibition  Model.  This  very 
simple  but  effective  device  automatically 

shuts  off  the  light  when  the  film  is  at  rest,  and  absolutely  prevents  the 
light  being  thrown  upon  the  film  except  when  the  latter  is  in  full  motion. 


Fig.  45 


Automatic   Shutter  for 
Exhibition  Model  of  Edison 
Kinetoscope 


159 


84  THE  MOTION  PICTURE 

This  shutter,  Fig.  45,  consists  essentially  of  two  parts:  a  film 
gate,  upon  which  is  mounted  a  metallic  shutter  and  centrifugal  gov- 
ernor, and  a  casting  upon  which  is  mounted  an  intermediate  gearing, 
through  wliich  the  shutter  is  connected  to  and  operated  by  the  large 
driving  gear. 

The  exliibition  automatic  shutter  is  not  regularly  furnished 
with  the  improved  exhibition  model  machine,  but  is  attached,  at  an 
extra  charge,  when  ordering  a  machine. 

Rheostats.  The  question  of  rheostats  is  one  about  which  there 
has  been  much  discussion  and  diversity  of  opinion,  due  principally 
to  a  lack  of  knowledge  of  real  conditions.  *It  is  not  practical  to  make 
what  might  be  termed  a  "universal  rheostat"  or  one  equally  well 
adapted  to  meet  all  conditions.  A  rheostat  with  a  capacity  of  25 
to  40  amperes  on  direct-current  circuits  of  100-125  volts  will  give 
perfectly  satisfactory  results  under  ordinary 

B-*  conditions   in    the   hands   of   an   intelligent 

^^        operator.     To   get  equally  satisfactory  re- 
'S^B        suits  with  alternating  current,  35  to  60  am- 
■fl        peres  are  required  with  the  same  line  volt- 
^H        age.    For  direct-current  circuits  of  100-125 
|H        volts,   the  Underwriters'  INIodel  (coil  type) 
^B        rheostat  is  recommended,  and  the  Under- 
Ml        writers'  Model  (type  "B")  for  altemating- 
•^^        current  circuits,  on  account  of  its  greater 
■^        capacity.     The  latter  will  give  equally  satis- 
Fig.  46    Coil  Type  Rheostat     factory  rcsults   ou   both   direct-  and   alter- 
nating-current circuits  of  100-125  volts,  hut 
on  direct-current  circuits  care  should  he  taken  to  adjust  it  so  that  not 
more  than  25  to  40  amperes  are  consumed  in  the  line. 

The  coil  type  rheostat.  Fig.  46,  is  regularly  furnished  with  the 
exliibition  model  projecting  Kinetoscope,  while  the  new  grid  type, 
Fig.  47,  is  supplied  with  the  Underwriters'  Model  machine. 

In  the  design  and  construction  of  the  grid  t}'pe  rheostat  the  old- 
style  wire  resistance  coils  have  been  discarded  and  replaced  with 
cast  metal  grids,  supported  and  insulated  by  water  and  fireproof 
material. 

The  rheostat  can  be  used  on  either  direct  or  alternating  current 
of  any  frequency,  with  equally  good  results,  and  in  either  case  a  max- 


160 


f 


MOTION  HEAD 


85 


imum  current  can  be  obtained  without  excessive  heating  on  a  line 
voltage  varying  from  100  to  125  volts. 

The  front,  back,  and  sides  are 
enclosed  with  solid  sheet  metal,  while 
the  top  and  bottom  are  enclosed  with 
perforated  sheet  metal. 

The  operating  switch,  switch 
contacts,  and  binding  posts  are  all      ^  —  jvjol 

inside  the  sheet  metal  frame  and  are  ' '"' 

thoroughly  protected    from    outside  ^ 

,       .       rrn  'ill,         11     •  i.   •  1  Fig-  47.     Grid  Type  Rheostat 

contact,    i  he  switch  handle  is  outside 

the  sheet  metal  case  and  a  pointer  indicates  the  position  of  the  switch. 


TABLE  I 
Projection  with  Edison  Lenses 

Project  a  picture  3  ft.  wide  for  every   10  feet  of  dis- 
tance. 


No.  1  M.  P.  Lens 

No.  4  "       " 

No.  lA  Stereo.  Lens 
No.  L\A       "       " 

No.  2  M.  P.  Lens 

No.  5  "       " 

Xo.  2A  Stereo  Lens 

No.  3  M.  P.  Lens 

No.  6  "       " 

No.  3 A  Stereo.  Lens 


Project  a  picture  3  ft.  wide  for  every  13  feet  of  dis- 
tance. 

Project  a  picture  3  ft.  wide  for  every  19  feet  of  dis- 
tance. 

THE  MOTIOGRAPH 


How  to  Install  or  Set  Up  the  Motiograph.  The  complete  ma- 
chine and  equipment  Fig.  48,  comes  packed  in  a  single  case.  Take 
out  all  the  parts  and  see  that  all  are  wiped  free  from  dust  and  that 
none  are  left  in  the  packing  case  or  overlooked  in  the  packing  ma- 
terial. 

The  mechanism  base,  lamp  house,  sliding  frame,  backward  and 
forward  slide  rods  and  brackets  are  screwed  to  the  baseboard.  The 
arc  lamp,  saddle,  post,  etc.,  will  be  found  inside  the  lamp  house. 

^Mien  the  pedestal  base  is  used  to  support  the  Motiograph 
it  should  be  fastened  very  firmly  to  the  floor  with  f-inch  lag  screws, 
large  square  head  wood  screws,  of  good  size,  and  care  should  be  taken 
to  see  that  as  nearly  as  po.ssibIe  contact  with  the  floor  is  had  on  all 
sides.     In  order  to  do  this,  as  a  rule,  it  is  advisable  to  use  wedges 


161 


86 


THE  IVIOTIQN  PICTURE 


of  hard  wood.  It  will  be  well  to  screw  the  base  tightly  to  the  floor 
and  then  drive  the  wedges  just  tight  enough  at  different  points  so  the 
base  will  rest  with  equal  pressure  on  all  sides. 

To  assemble  the  equipment  set  the  lamp  house  in  position  on  the 
lamp  house  slide  frame,  and  insert  the  two  cross  slide  rods  through 


Fig.  48.     Details  of  Motiograph 

the  ears  on  both  the  lamp-house  base  and  the  sliding  frame,  screw- 
end  first,  and  screw  them  into  the  ears  in  the  sliding  frame  that  comes 
next  to  the  operator,  which  is  the  right  side  when  looking  from  the 
rear  toward  the  front  of  the  instrument.  Set  the  Motiograph  mech- 
ani.'-m  on  the  circular  swivel  base  2  and  screw  down  the  swivel 
thumb  wheel.     (Cut  above  shows  the  1908  and  1909  Models  with 


162 


MOTION  HEAD 


87 


thumb  wheel  12  on  top  of  the  base.  The  thumb  wheel  for  the  1910 
Model  is  larger  and  is  under  the  base.)  Attach  the  upper  reel  arm 
7 A  by  entering  the  shaft  and  cross  pin  into  the  rewind  vertical  socket 
arbor,  and  screw  into  place  with  the  three  reel  arm  thumb  screws 
128.  Attach  the  take-up  or  lower  reel  arm  9A,  Fig.  49,  with  the 
three  reel-arm  thumb  screws  237.  Place  the  take-up  belt  in  posi- 
tion on  the  take-up  pulleys  with  the  idler  pulley  under  the  belt,  first 
having  loosened  the  tension  screw  of  the  belt  idler  109  until  the  belt 
is  quite  loose. 

Remove  the  objective  lens  from  the  litde  pasteboard  box  and 
screw  it  into  position  on  the  front  plate  of  the  mechanism,  first  having 
removed  with  a  soft  cotton  handkerchief  any  dust  that  may  have  ac- 
cumulated on  either  the  front 
or  rear  surface  of  the  lens.  Be 
sure  that  the  extension  collar 
is  in  place,  if  the  lens  is  of  such 
focus  that  it  requires  one. 
Otherwise  the  lens  can  be 
brought  to  the  focal  point. 
Place  the  framing  lever  han- 
dle 75  in  the  framing  lever 
socket  11,  and  screw  it  into 
place.  Loosen  the  little  thumb 
screw  on  the  crank  13 A,  place 
the  crank  in  position  on  the 
crank  arbor  and  tighten  the  little  thumb  screw  on  the  crank  so  it 
engages  with  the  groove  in  the  crank  arbor  to  hold  the  crank  in 
place.  Remove  the  stereopticon  lens  bracket  screw  and  attach 
the  stereopticon  lens  bracket  37.  Attach  the  stereopticon  lens  ring 
to  slide  rod  on  stereopticon  lens  bracket,  tightening  into  place  widi 
the  thumb  screw.  Remove  the  stereopticon  lens  from  its  box,  care- 
fully wipe  from  the  surface  of  the  lens  any  dust  that  may  have  ac- 
cumulated, remove  the  flange  ring  from  the  lens.  Insert  it  back  of 
the  lens  ring  with  the  bead  or  rim  to  the  front;  insert  the  lens  and 
screw  it  in  place.  It  is  unnecessary  to  have  the  flange  ring  at- 
tached to  the  cast  ring  or  to  have  the  cast  ring  threaded. 

The  location  of  the  stereopticon  objective  lens  on  the  rod  support 
should  be  such  that  the  distance  from  about  the  center  of  the  lens 


Fig.  49.     Take-Up  Device 


163 


88  THE  MOTION  PICTURE 

(from  front  to  back)  and  the  front  surface  of  the  front  condensing 
lens  is  equal  to  the  focal  length  of  the  lens.  For  example,  a  stereop- 
ticon  lens  of  122^-inch  focus  should  be  located  so  that  the  distance 
from  the  middle  of  the  stereopticon  objective  lens  to  the  front  of  the 
condensing  lens  is  about  12  inches  when  the  rack  adjustment  of 
the  lens  is  so  set  that  it  will  allow  of  liberal  adjustment  in  either 
direction.  The  stereopticon  lens  bracket  rod  may  be  screwed  into 
either  the  front  or  the  rear  of  the  bracket  depending  on  the  focal 
length  of  the  lens. 

The  universal  reel  clamp  is  used  for  the  1908  and  1909  Models 
No.  1  and  No.  2  machines  It  will  be  found  clamped  on  the  reel 
arbor.  This  should  be  removed  by  holding  the  clamp  with  one 
thumb  and  finger  and  loosening  the  thumb  screw  with  the  other. 
This  will  loosen  the  clamp  and  it  may  be  slipped  off  the  arbor. 
Now  put  the  reels  in  place  on  the  arbor,  and  turn  around  until  the 
key  pin  on  the  arbor  enters  the  seat  (hole  or  keyway)  in  the  reel. 
Slip  on  the  universal  clamp  with  the  projecting  pin  next  to  the  reel, 
insert  the  pin  into  the  ke}'way  or  slot  in  the  core  block  of  the 
reel,  and  tighten  the  clamp  thumb  nut,  which  will  hold  the  reel  se- 
curely on  the  arbor.  The  vmiversal  reel  clamp  has  been  dispensed 
with  for  the  ]Model  No.  lA  for  1910  and  a  new  arrangement  called 
a  jointed  red  shaft  latch  is  used. 

AMien  fireproof  magazines  are  to  be  used,  they  should  be  at- 
tached before  the  reels  are  put  in  place.  To  attach  the  fireproof 
magazines  unscrew  the  two  thumb  screws  in  the  magazine  spiders 
£6,  so  as  to  let  their  points  pass  the  flange  on  the  reel  arm,  put  the 
magazine  in  place  on  the  reel  arm  by  inserting  the  boss  on  the  reel 
arm  into  the  opening  of  the  spider.  Have  the  fire  trap  or  valve 
toward  the  upper  or  lower  feeding  sprocket  (depending  on  which 
of  the  reel  arms  you  are  assembling),  tighten  the  thumb  screws  to 
engage  the  flange  on  the  reel  arm.  Now,  open  the  magazine  and 
attach  the  reel  in  the  same  manner  as  in  instructions  previously  given. 
The  magazines  are  marked  on  the  inside  "upper"  or  "lower." 

The  condensing  lenses  are  mounted  in  a  nickel-plated  mount 
and  are  held  in  by  the  use  of  two  inside  telescopic  bands.     The  con- 
denser mount  is  held  in  position  on  the  front  of  the  lamp  house  by 
two  clamps  and  two  screws.     The  mount  may  be  removed  from  the        I 
lamp  house  front,  for  changing  or  cleaning  the  lenses,  by  turning  the 


164 


MOTION  HEAD 


'dd 


two  clamps  until  the  flattened  sides  of  the  clamps  come  next  to  the 
flange  of  the  condenser  mount.  The  mount  is  usually  left  attached 
to  the  lamp  house  for  shipment.  The  flat  side  of  the  condensers 
should  always  be  outward  and  the  convex  sides  toward  each  other. 
The  surfaces  of  the  condensing  lenses  should  be  free  from  dust,  per- 
spiration, or  other  accumulations  to  insure  the  unobstructed  pas- 
sage of  the  light. 

The  No.  lA  1910  framing  device,  Fig.  50,  can  be  used  in  the 
1909  No.  1  or  No  2  mechanisms  by  buying  the  short  connecting  link 
107A  to  connect  the  framing  handle  with  the  framing  device,  and  the 
1909  framing  device,  Fig.  51,  may  be  used  in  the  1910  machine  by 
using  the  1909  link  167.  Both  framing  devices  are  practically  alike 
with  the  exception  of  the  vertical  casting,  which  can  be  interchanged 


Fig.  50.     Motiograph  lA  1910  Model  Framing  Device 

between  the  two,  and  the  change  can  be  made  from  one  to  the  other 
by  removing  the  four  screws  in  the  side. 

Attach  the  stereopticon  slide  carrier  to  the  lamp-house  slide 
carrier  swing  310,  and  clamp  in  position  with  the  thuml)  screw  on 
top  of  the  carrier  swing.  If  the  lamp  house  cone  377  has  been  re- 
moved for  convenience  in  packing  for  transit,  it  is  to  be  attached  by 
inserting  the  two  dowel  pins  in  lamp-house  support  306  and  will  be 
held  in  place  by  the  two  small  thumb  screws  on  the  side  of  the  cone 
support. 

Test  the  slide  on  the  lamp  house  and  see  that  it  slides  freely  on 
the  backward  and  forward  and  the  sidewise  movements. 

The  proper  adjustment  for  the  lamp  house  on  the  backward 
and  forward  sHde  should  be  a  point  where  the  distance  between  the 


165 


90 


THE  MOTION  PICTURE 


front  face  of  the  condensing  lenses  and  the  film  on  mechanism  will 
be  about  12t  inches  when  operating  at  a  distance  of  about  60  feet 
from  the  screen  with  a  picture  of  moderate  size.  AMien  operating 
a  greater  distance  from  the  screen,  the  distance  between  the  conden- 
sing lenses  and  the  aperture  plate  should  be  greater,  depending 
on  the  length  of  focus  of  the  condensing  and  objective  lenses  that 
are  being  used  and  the  individual  preference  of  the  operator.  Some 
operators  prefer  a  greater  distance  between  condensers  and  film, 
even  when  operating  at  the  above  distance  from  the  screen. 


6  ZIS 


k  'tff^r^'^.  ^:)^ 


-ZiS'' 


Fig.   51.      Motiograph     No.  2,  1908  and 
1909  Framing  Device 

Motiograph  Lens  Adjustment.  The  lens  should  give  a  sharp 
focus  on  the  screen  giving  clear  detail.  If  the  lens  does  not  give  a 
sharp  focus  after  turning  the  focusing  ring  to  both  extremes  of  ad- 
justment, it  will  be  an  indication  that  the  extension  collar  used  is 
either  too  long  or  not  long  enough,  in  which  case  test  may  be  made  by 
unscrewing  the  lens  from  the  collar  and  holding  it  by  the  hand,  shift- 
ing to  different  distances  from  the  film  to  determine  what  position  is 
necessary  to  give  a  sharp  focus.  The  use  of  mica  with  scratches 
on  it  for  the  test  focusing  is  recommended. 

Open  the  film  gate,  swing  it  to  the  left,  tuni  the  crank  of  the  mo- 
tion-picture machine  so  the  leaves  of  the  shutter  do  not  cover  the 
opening  in  the  aperture  plate,  so  as  to  allow  a  free  passage  for  the 
light  through  the  aperture  plate  and  the  objective  lens.  This  should 
be  done  before  the  film  is  placed  in  the  machine. 


166 


MOTION  HEAD 


91 


The  objective  lens  on  the  front  of  the  motion-picture  machine 
should  now  be  focused  by  turning  the  focusing  ring  until  the  square  of 
light  on  the  screen  is  sharply  defined;  that  is,  the  margin  of  the  light 
opening  should  be  clean  and  sharp  and  not  fuzzy.  \Mien  this  is 
done  only  a  slight  adjustment  is  recjuired  to  focus  the  picture  sharply 
when  the  film  is  in  place.  All  of  the  above  adjustments  should  be 
accompHshed  before  the  film  is  placed  on  the  machine.  Some 
operators  use  a  piece  of  mica  on  which  some  sharp  scratches  have 
been  made  with  a  knife,  for  the  purpose  of  getting  a  sharp  focus 
before  the  film  is  put  in  place.  A  piece  of  ruled  mica  is  furnished 
with  each  Motiograph. 

WTien  using  the  Motiograph  equipped  with  the  automatic  fire 
shutter,  it  will  be  necessary  to  open  the  film  gate  when  doing  the  pre- 
liminary focusing  of  the  objective  lens,  and  to  see  that  the  illumina- 
tion on  the  screen  shows  a  clear  outline  of  the  margin  of  the  aperture 
plate. 


Position  of  Crank  of 
Motiograph  When 
Showing  Pictures 


Fig.  52. 


Position  of  Crank  of  Motio- 
graph When  Rewinding 
Films 


Threading  the  Film.  ^^Tlen  film  is  received  from  the  manu- 
facturers wound  in  a  roll,  the  center  of  which  is  too  small  to  admit 
the  core  block  of  the  reel^  it  is  necessary  to  rewand  it.  This  may 
be  done  by  removing  the  lower  reel  from  the  arbor,  place  the  roll  of 
film  on  the  bare  arbor,  insert  the  outer  end  of  the  film  under  the  spring 
clip  on  the  core  block  of  the  upper  reel,  and  wind  the  film  on  the 
upper  reel. 

To  shift  the  connection  between  the  crank  and  the  reel  arbor 
when  using  the  :Model  No.  1  for  1909  or  No.  lA  for  1910,  all  that 
is  necessary  is  to  press  a  spring  plunger  at  the  right  of  the  crank  boss 
of  the  main  frame.  Fig.  52,  turn  the  crank  slightly,  pull  it  toward 
you  about  y\  of  an  inch,  and  the  spring  bolt  will  automatically  drop 


167 


92 


THE  MOTION  PICTURE 


into  the  other  groove  and  hold  the  crank  in  place  for  rewinding  the 
film,  Fig.  53. 

After  the  film  has  been  wound  on  the  upper  reel,  remove  the 
upper  reel  and  place  it  on  the  take-up  below.  Place  another  reel  on 
the  upper  reel  arm,  take  the  outer  end  of  the  film  (which  was  on  the 
inside  of  the  roll  when  received),  pass  it  to  the  rear  of  the 
upper  reel,  inserting  the  end  under  the  spring  clip^  and  again  wind 
the  film  on  the  top  reel,  making  sure  that  the  emulsion  or  dull  side 
of  the  film  is  wound  toward  the  outside. 

^\Tien  the  film  has  been  wound 
back  on  the  upper  reel,  press  the 
spring  plunger  and  return  the 
crank  to  its  normal  position. 
\^^len  using  this  form  of  reeling 
mechanism  in  combination  with 
fireproof  film  magazines,  it  is 
unnecessary  to  remove  either  the 
magazines  or  the  reels  for  re- 
winding; in  fact,  with  reasonable 
care  and  by  the  use  of  a  few  feet 
of  white  undeveloped  film  on 
each  end  of  the  picture  film  as 
leaders,  the  operator  will  see  that 
the  film  is  nearing  the  end,  and 
it  can  be  run  and  rewound  time 
after  time  and  it  will  not  be 
necessary  to  disconnect  the  film 
from  either  reel  until  the  film  is  to  be  changed  for  a  different  subject. 
Draw  from  the  reel  a  length  of  about  2  feet  of  film,  press  the 
handle  of  the  upper  sprocket  roller  bracket  2If.  to  the  left  as  far  as 
it  will  go,  pass  the  film  under  the  sprocket  wheel,  so  that  the  teeth 
of  the  wheel  engage  in  the  perforations  of  the  film,  and  press  the  top 
of  the  roller  bracket  to  the  right  until  the  roller  comes  into  place 
against  the  sprocket  wheel  and  holds  the  film  in  place.  The  roller 
brackets  should  not  press  tightly  against  the  film,  and  there  should 
be  just  room  enough  between  the  roller  and  the  sprocket  wheel  for 
the  film  to  pass  without  being  pressed.  The  adjustment  of  these 
rollers  is  accomplished  with  the  screw  203  and  check  nut.     This 


Motiograph  Rewinding 


168 


MOTION  HEAD  93 

adjustment  is  always  properly  set  before  the  machines  leave  the 
factory,  and  should  not  require  any  further  attention  until  the  rollers 
have  become  somewhat  woni,  unless  some  one  tampers  with  the 
machine.    However,  it  is  well  to  keep  this  adjustment  in  mind. 

Press  the  film  gate  latch  154  to  open  the  gate,  swing  the  gate 
back,  raise  the  intermittent  sprocket  roller  bracket  23  until  it  stands 
in  a  horizontal  position,  lay  the  film  on  the  aperture  plate  in  such 
a  position  as  to  leave  a  loop  at  the  top,  as  indicated  by  the  word 
"loop,"  and  return  the  intermittent  roller  bracket  to  its  original 
position,  to  hold  the  film  in  place  on  the  sprocket  teeth  of  the  inter- 
mittent sprocket. 

The  intermittent  roller  bracket  has  a  screw  adjustment  the  same 
as  those  of  the  upper  and  lower  roller  brackets,  except  that  it  has  a 
check  screw  instead  of  a  check  nut  to  hold  the  adjustment. 

Press  downward  on  the  handle  of  the  lower  roller  bracket,  pass 
the  film  over  the  lower  feeding  sprocket  wheel,  leaving  a  loop  between 
the  intermittent  and  the  feeding  sprocket  as  indicated  by  the  word 
"loop"  in  Fig.  48.  See  that  the  teeth  engage  the  sprocket  holes  in 
the  film  and  turn  the  roller  bracket  to  place.  Pass  the  loose  end  of 
the  film  over  the  core  block  of  the  lower  take-up  reel  and  under  the 
end  of  "the  spring  clip. 

A\Tien  threading  the  film,  place  the  framing  lever  about  the  mid- 
dle of  the  two  extremes  of  its  up  and  down  movement,  for  by  so  doing 
the  upper  and  lower  loops  may  be  properly  proportioned  so  as  not 
to   require  rearrangement. 

Turn  the  handle  of  the  machine  over  to  the  right  toward  the 
front  of  the  machine  at  the  rate  of  about  one  revolution  per  second. 
The  exact  speed  at  wliich  the  handle  should  be  turned  will  readily 
be  determined  by  the  movements  of  the  figures  in  the  pictures,  which 
should  be  normal  and  natural,  and  by  the  flicker,  which  must  not  be 
too  great. 

\Miile  the  machine  is  in  motion  test  both  bottom  and  top  loop 
to  see  that  they  are  sufficiently  long.  Take  hold  of  the  framing  lever 
handle  75,  swing  it  up  and  dowai  (while  the  machine  is  in  motion 
only)  as  far  as  it  will  go,  and  when  at  the  two  extreme  positions  there 
should  still  be  a  small  loop  remaining.  If  the  loop  is  entirely  taken 
up,  the  roller  bracket  should  be  opened  and  the  loop  extended  suf- 
ficientlv.     If  this  is  not  done  the  film  may  be  torn.     You  are  now 


169 


94  THE  MOTION  PICTURE 

ready  to  start.  The  loops  should  not  be  too  long  as  they  have  a 
tendency  to  vibrate  considerably,  which  may  make  the  pictures 
unsteady. 

It  is  important  when  rimning  new  film  to  scrape  off  the  spots 
of  film  emulsion  that  collect  on  the  film  tension  springs  and  the  ribs 
of  the  aperture  plate.  These  accumulations,  if  allowed  to  remain, 
have  a  tendency  to  not  only  scratch  the  film,  but  make  it  run  unsteady, 
and  are  liable  to  be  the  cause  of  slightly  tearing  the  corners  of  the 
sprocket  holes  in  the  film,  besides  making  the  machine  run  heavy, 
with  increased  wear  to  the  parts.  A  silver  dime  is  a  good  instru- 
ment to  use  for  scraping  them.  On  the  first  run  film,  the  tension 
springs  should  be  scraped  before  starting  to  make  each  run  of  a 
thousand  feet.  Do  not  scrape  the  springs  with  a  knife  or  other  steel 
instrument,  as  it  would  be  liable  to  leave  a  rough  surface  on  the  ten- 
sion parts  that  would  injure  the  film. 

Instructions.  To  remove  the  front  of  the  Motiograph  loosen 
the  two  thumb  screws  at  the  bottom,  lift  up  the  spring  at  the  top 
while  pulling  the  front  plate  forward  sufficiently  to  disengage  the 
spring,  and  lift  it  up  to  disengage  it  from  the  thumb  screws  below. 

Adjustments.  There  are  four  important  adjustments  in  the 
Motiograph  that  it  will  be  necessary  for  the  operator  to  concern 
himself  with. 

(1)  The  adjustment  of  the  idler  on  the  take-up  belt  should 
be  just  tight  enough  to  make  sure  that  the  film  will  be  wound  up  on 
the  reel  as  fast  as  it  comes  through  the  machine.  If  too  tight  it  will 
pull  too  hard  on  the  film,  with  the  result  that  it  is  liable  to  tear  the 
sprocket  holes.  The  flexible  broad  flat  belt,  in  combination  with  the 
adjustable  idler,  furnishes  a  most  sensitive,  yet  positive,  means  of 
taking  up  the  film  without  doing  injury  to  it.  When  the  idler  is 
adjusted,  the  check  nut  on  the  screw  should  always  be  tightened 
so  as  to  retain  the  adjustment.  If  the  belt  is  too  tight  when  the 
tension  is  oft",  stretch  it  by  pressing  the  two  sides  together  near  the 
large  pulley. 

(2)  The  adjustment  of  the  sprocket  rollers  or  idlers  should  be 
given  careful  attention.  There  should  be  just  room  enough  for  the 
film  to  pass  freely  between  the  roller  and  the  sprocket  without  pres- 
sure on  the  film.  The  film  rollers  are  adjusted  to  position  by  a  set 
screw  that  passes  through   the  roller  bracket.     After  the  screw  is 


170 


SI 


MOTION  HEAD 


95 


properly  adjusted  the  check  nut  or  check  screw,  as  the  case  may  be, 
should  be  tightened  so  as  to  retain  the  adjustment. 

(3)  The  Geneva  movement  that  operates  the  intermittent 
film  sprocket  wheel,  called  the  star  and  cam,  will  need  to  be  adjusted 
only  after  it  is  worn  to  such  an  extent  that  the  intermittent  sprocket 
wheel  can  be  slightly  turned  when  at  rest;  that  is,  when  the  pin  in 
the  Geneva  driver  or  pin  wheel  is  on  the  opposite  side  of  the  pin  wheel 
from  the  star  wheel.  The  adjustment  is  accomplished  by  the  two 
set  screws  that  clamp  the  eccentric  bushing  in  position.  To  set 
the  Geneva  parts  closer  together,  loosen  the  lower  set  screw  very 
slightly  and  tighten  the  upper  screw.  Have  the  adjustment  of  the 
Geneva  driver,  cam,  or  pin  wheel  just  close  enough  to  the  star  wheel 


Fig.  54.     Motiograph  Safety  Shutter 

that,  the  movement  of  the  pin  wheel  shaft  will  be  free  and  easy, 
yet  so  there  will  be  no  circular  movement  to  the  intermittent  sprocket 
wheel  while  it  is  at  rest.  Do  not  tighten  so  the  cam  or  pin  wheel 
will  not  work  perfectly  freely. 

The  governor  that  operates  the  fireproof  shutter  may  be  removed 
from  the  Motiograph  if  necessary  by  removing  the  bushings  at  each 
end  of  the  governor  shaft  or  arbor,  or  by  removing  the  gear  bridge 
and  the  inside  bushing.    The  bushings  are  held  in  place  by  set  screws. 

(4)  The  adjustment  of  the  governor  and  fireproof  shutter, 
Fig.  54,  is  accomplished  by  sliding  endwise  the  pivot  bushings  in 
the  frame.  To  adjust,  loosen  the  screws  that  hold  both  bushings, 
hold  the  two  between  the  thumb  and  finger  and  slide  them  slightly 
out  and  in  when  the  machine  is  running  at  regular  speed,  until  the 
point  is  reached  where  the  fireproof  shutter  will  be  raised  clear  up, 
and  at  the  same  time,  the  little  bar  which  connects  the  shutter  with 
the  governor  crank  bar  will  rest  loosely  on  the  governor  crank  pivot. 


171 


96  THE  MOTION  PICTURE 

In  no  instance  should  it  be  drawn  tight.  Now  tighten  the  screw  on 
the  inside  bushing,  then  loosen  the  outside  bushing  just  enough 
so  the  governor  will  work  freely,  and  tighten  the  screw  on  that 
bushing. 

Don't  adjust  the  governor  too  tight;  if  too  tight,  the  machine 
will  run  hard  and,  besides,  the  wear  will  be  excessive. 

Oiling.  It  is  absolutely  necessary  that  a  motion-picture  machine 
be  kept  well  oiled,  in  order  to  keep  it  in  good  condition,  and  that 
it  may  do  good  work.  Remember  that  while  in  operation  the  bal- 
ance wheel  shaft  and  Geneva  action,  which  operates  the  intermittent 
sprocket,  is  making  nearly  1,200  revolutions  per  minute,  or  72,000 
revolutions  per  hour,  and  that  when  giving  fifteen  shows  per  day, 
of  twenty  minutes  each,  the  balance  wheel  and  Geneva  action  has 
made  360,000  revolutions.  No  machine  can  be  expected  to  endure 
such  work  without  proper  care.  Be  sure  that  all  of  the  bearings  are 
oiled  and  that  none  have  been  overlooked. 

^Vhen  running  afternoon  and  evening  all  of  the  bearings  should 
be  oiled  twice  during  the  day,  besides  which  the  Geneva  movement 
and  governor  shaft  pivots  should  be  oiled  after  every  other  show, 
or  make  sure  that  there  is  a  sufficient  amount  of  oil  in  the  Geneva 
movement  casing,  that  the  Geneva  movement  is  kept  constandy 
lubricated. 

It  is  important  that  the  oiling  should  be  carefully  done,  and 
that  none  of  the  bearings  should  be  overlooked.  It  is  advisable  to 
establish  a  practice  of  always  oiling  the  bearings  in  the  same  order, 
as  in  this  way  you  will  be  less  liable  to  overlook  any  of  them.  Care 
should  be  exercised  not  to  have  any  oil  on  the  sprocket  wheels  and 
on  the  film  pressure  rollers,  as  oil  in  these  places  would  be  trans- 
mitted to  the  film  and  badly  damage  it.  All  surplus  oil  remaining 
on  the  outside  of  the  oil  holes,  or  in  other  places  where  it  might  come 
in  contact  with  the  film,  should  be  carefully  removed  with  a  soft 
cotton  cloth. 

The  quality  of  oil  used  on  a  motion-picture  machine  is  of  great 
importance.  Do  not  get  the  impression  that  anything  sold  under 
the  name  of  oil  is  good  enough.  Never  oil  with  kerosene  or  any 
oil  that  is  highly  adulterated  with  kerosene,  as  it  has  practically  no 
lubricating  properties.  Do  not  use  ordinary  lard  oil  that  is  adapted 
to  use  on  heavy  machinery;  it  is  too  coarse  and  will  gum  the  bearings. 


172 


MOTION  HEAD  97 

There  are  oils  on  the  market,  some  of  which  are  extensively  adver- 
tised and  are  recommended  for  lubricating,  polishing  furniture,  and 
as  rust  preventives,  etc.,  that  are  not  at  all  suitable  for  the  lubri- 
cation of  a  motion-picture  machine.  Sewing-machine  oil  of  fine 
grade  is  most  desirable,  and  the  best  place  to  get  it  is  at  a  sewing- 
machine  agency.  A  cheap  grade  of  sewing-machine  oil  should  not 
be  used  owing  to  its  poor  quality  as  a  lubricant. 

Vaseline  is  used  in  the  framing  device  oil  chamber.  Remove 
that  part  of  the  framing  device  which  forms  the  cover  to  t^ie  oil 
chamber  by  removing  the  four  screws  in  the  side.  Take  the  remain- 
ing part  of  the  framing  device  in  one  hand,  and  with  the  flexible 
metal  tube  of  white  vaseline  in  the  other,  force  the  vaseline  into  the 
opening  of  the  flange  of  the  pin  wheel,  where  the  pin  is  located  until 
that  opening  is  well  filled,  then  force  the  vaseline  all  around  the 
outside  of  the  flange  of  the  pin  wheel.  Then  cover  the  entire  surface 
of  the  star  with  a  liberal  coating.  This  is  all  that  will  be  required. 
Care  must  be  taken  not  to  put  in  too  much  vasehne,  as  the  rapid 
rotation  of  the  star  and  cam  wheel  will  have  a  tendency  to  force  it 
out  through  the  oil  cup,  which  would  be  very  undesirable. 

After  replacing  the  cover  put  eight  or  ten  drops  of  fine  lubricat- 
ing oil  in  the  oil  cup  on  top  of  the  framing  device,  which  will  mix 
with  the  vaseline  and  soften  it  to  the  proper  consistency.  If  care 
has  been  taken  in  applying  the  vaseline  thoroughly  the  machine 
should  run,  even  under  the  heaviest  usage,  for  at  least  three  weeks 
without  further  attention  to  this  part,  except  to  add  occasionally  a 
few  drops  of  fresh  oil.  At  the  end  of  that  period,  if  the  vaseline  has 
become  blackened,  it  is  time  to  remove  it,  clean  the  pin  and  star  wheel, 
wash  them  off  with  benzine  or  gasoline  and  put  in  fresh  vaseline  as 
described  above. 

Vaseline  is  used  as  a  lubricant  for  the  star  and  pin  wheel  and  is 
without  an  equal  for  the  Motiograph.  It  is  necessary,  however,  to 
avoid  the  cheap  qualities  put  up  in  bulk,  and  never,  under  any  cir- 
cumstances, use  carbolated  vaseline.  Use  the  white  vaseline  put 
up  in  flexible  metal  tubes,  which  may  be  had  at  drug  stores  or  it 
may  be  ordered  of  the  manufacturers  of  the  Alotiograph. 

When  oil  only  is  u^ed  without  vaseline  it  is  preferable  to  use  a 
very  heav}'^  oil  of  fine  quality,  rather  than  a  thin  oil. 

To  keep  a  machine  in  good  condition  it  should  occasionally 


173 


98  THE  MOTION  PICTURE 

have  the  working  parts  cleaned  with  gasoline  to  remove  dirt,  gum, 
and  old  oil,  the  parts  wiped  dry  with  a  soft  cotton  cloth,  and  fresh 
oil  applied. 

The  high-speed  spindles  of  the  Motiograph  all  run  in  inter- 
changeable phosphor-bronze  bearings.  These  may  be  replaced  with 
new  ones  when  worn.  Phosphor-bronze  is  one  of  the  best  anti- 
friction metals  known,  and  with  proper  care  none  of  the  bearings 
should  need  replacing  for  a  long  time. 

The  fire-trap  rollers  should  be  kept  clean.  In  case  the  film  should 
become  ignited  and  the  flame  extend  to  the  fire  trap  or  valve,  some 
of  the  melted  celluloid  is  liable  to  stick  to  the  rollers  and  when  dry 
it  becomes  very  hard  and  brittle  and  would  do  much  damage  to  the 
film  if  allowed  to  remain.  In  a  case  of  this  kind  the  rollers  should 
be  carefully  cleaned.  The  rollers  should  also  be  cleaned  from  time 
to  time  to  keep  them  free  from  accumulations  of  dust,  oil,  etc.,  which 
will  do  more  or  less  injury  to  the  film.  Alcohol  or  refined  benzine 
is  good  for  the  purpose. 

The  belt  idler  adjustment  screw  is  provided  with  two  check 
nuts,  the  purpose  of  which  is  that  when  the  desired  adjustment  has 
been  secured,  one  nut  may  be  locked  against  the  other,  in  order  that 
the  screw  together  with  the  nuts  locked  in  position  on  the  screw, 
may  be  loosened  while  the  film  is  being  rev/ound,  as  otherwise  the 
pull  would  be  too  heavy  on  the  film  if  the  tension  was  allowed  to 
remain  the  same  as  when  the  film  is  being  taken  up  on  the  rewind. 
After  rewinding,  the  adjustment  screw  may  be  instantly  returned  to 
its  former  position. 

If,  for  any  reason,  it  should  become  necessary  to  remove  the 
gear  bridge  of  the  1908  or  1909  models,  the  disconnecting  of  the  gears 
would  throw  the  shutter  out  of  time  until  the  shutters  are  reset — 
that  is,  the  wings  of  the  shutter  would  not  cut  off  the  light  at  the 
proper  moment  with  relation  to  the  movement  of  the  film,  the  result 
of  which  would  be  to  show  a  ghost,  especially  on  the  announcements. 
This  would  not  occur  with  the  1910  No.  lA  model.  The  shutteT 
might  also  be  thrown  out  of  time  from  coming  in  contact  with  some- 
thing inserted  within  the  frame  while  the  shutter  is  in  motion. 

Setting  the  Motiograph  Shutters.  Setting  the  Intermittent  Double 
No.  1  Cone  Shutters  o)i  the  No.  lA  Motiograph,  Model  1910,  Fig.  55. 
The  instructions  for  setting  the  double  shutters  of  the  No.  lA  Motio- 


174 


* 


MOTION  HEAD 


99 


graph  for  1910  are  different  from  the  instructions  for  the  shutters 
of  the  No.  1  Models,  1908  and  1909.  The  reason  for  the  difference 
is  that  in  the  1908  and  1909  Models  the  movement  of  the  shutters 
is  in  the  opposite  direction  to  those  of  the  1910  Model. 

The  principle  of  setting  the  shutters  for  the  ^Motiograph  is  the 
same  as  for  any  other  moving-picture  machine,  that  is,  the  larger 
wings  of  the  shutters  should  cover  the  light  opening  or  aperture  dur- 
ing the  time  that  the  intermittent  sprocket  and  film  are  in  motion, 
and  the  smaller  wings  should  pass  during  the  exposure  while  the  film 
is  at  rest,  Figs.  56  and  57. 

To  set  the  shutters,  remove  the  front  plate,  which  carries  the 
lens,  after  which  remove  the  outer  shutter  wing  (the  one  nearest  you). 


Fig.  55. 


Sectional  View  of  the  Intermittent  Shutter  Arrangement  of  the 
Model  No.  lA,  1910  Motiograph 


loosen  the  screws  on  the  inner  shutter,  leaving  the  shutter  just  loose 
enough  to  be  turned  easily  by  hand,  and  tight  enough  so  it  will  not 
move  of  its  own  accord.  Remove  the  gear  cover,  after  which  take 
hold  of  the  balance  wheel  and  turn  the  mechanism  in  the  same  direc- 
tion as  during  the  operation  of  the  machine;  turn  very  slowly  until 
the  intermittent  sprocket  wheel  starts  to  move,  after  which  set  the 
upper  edge  of  the  large  wing  of  the  inner  shutter  about  Ae  inch  below 
the  center  of  the  aperture  plate  when  looking  on  a  line  parallel  through 


176 


100 


THE  MOTION  PICTURE 


the  center  of  the  light  aperture.  These  measurements  refer  to  the 
36-degree  shutters.  Now  revohe  the  mechanism  slowly  in  the  same 
direction,  obseiTing  when  the  intermittent  sprocket  wheel  stops  that 
the  lower  edge  of  the  large  unng  of  the  inner  shutter  is  about  ^  inch 
above  the  center  of  the  aperture  plate. 


Fig.  56.  Fig.  57. 

Motiograph  Shutter  in  Two  Positions 

Tio-hten  the  screws  firmly,  after  which  revolve  the  mechanism 
until  the  inner  shutter  is  at  the  original  position,  that  is,  the  upper 
edce  of  the  large  wing  should  be  about  ^e  inch  below  the  center  of 
the  aperture  plate.  Replace  the  outer  shutter  on  the  shaft,  tighten 
the  screws  partially  in  the  same  manner  as  was  done  with  the  inner 


Fig.   58.  Fig    59. 

Motiograph  Double  Shutter  in  Two  Positions  of  Adjustment 

shutter,  set  the  lower  edge  of  the  large  wing  about  Se  inch  above 
the  center  of  the  aperture  plate,  after  which  tighten  the  screws  firmly, 
Figs.  58  and  59. 

After  the  setting  of  the  shutters  has  been  once  done,  it  ^411  be 
very  simple  and  easy  to  repeat. 

The  width  of  the  shutter  wings  that  ^\^ll  be  furnished,  unless 
otherwise  ordered,  will  be  that  known  as  the  3G-degrce  wings,  wliich 


176 


MOTION  HEAD  101 

are  best  adapted  to  distances  from  60  to  100  feet  or  more.  The 
36-degree  wings  are  narrower  than  the  42-degree  wings  and  give 
the  greatest  possible  amount  of  exposure  as  compared  with  the  non- 
exposure.  On  distances  less  than  60  feet,  and  especially  where 
brilliantly-colored  announcements  are  used,  such  as  a  brilliant  red, 
there  is  liable  to  be  a  slight  ghost  of  color  above  and  below  the  an- 
nouncement. Also  where  there  are  plain  whites  in  the  picture, 
with  heavy  backgrounds  around  them,  there  is  liable  to  be  a  slight 
ghost. 

These  defects  being  so  slight  are,  to  most  exliibitors,  not  objec- 
tionable in  view  of  the  advantage  of  a  greater  amount  of  exposure, 
but  where  they  are,  they  may  be  entirely  overcome  by  use  of  the  42- 
degree  shutters,  the  wings  of  which  are  wider  than  the  32-degree. 

To  Set  the  No.  2  Motiograph  Shutter.  Remove  front  plate 
which  carries  lens,  loosen  screws  in  shutter  just  enough  so  shutter 
can  be  easily  turned  on  the  shaft.  Take  hold  of  the  balance  wheel, 
revolve  mechanism  in  same  direction  as  during  operation  of  the  ma- 
chine, observe  when  the  intermittent  sprocket  starts  to  move  and 
set  lower  edge  of  shutter  at  bottom  edge  of  aperture.  Turn  the  bal- 
ance wheel  until  the  sprocket  stops,  at  which  time  the  top  edge  of 
shutter  should  be  on  a  hue  with  the  top  edge  of  the  aperture.  When 
properly  set,  tighten  the  screws  in  shutter. 

Lenses  of  shorter  focus  than  about  2f  inch  cannot  be  used  to 
advantage  w^ith  the  regular  ]\Iotiograph  double  or  single  cone  shut- 
ters, and  when  lenses  of  shorter  focus  than  about  2|  inch  are  to  be 
used,  we  recommend  the  use  of  the  Auxiliary  front  intermittent 
shutter  No.  3,  which  may  be  attached  to  and  used  with  the  No.  lA 
mechanism,  the  first  of  which  were  placed  on  the  market  in  April, 
1910.  With  this  form  of  shutter  there  is  no  limit  and  lenses  of  as 
short  focus  as  may  be  desired  can  be  used.  Extreme  short  focus 
lenses  should  never  be  used  where  the  machine  could  be  set  at  a 
point  where  longer  focus  lenses  can  be  used,  and  especially  where 
the  machine  is  to  be  located  considerably  above  or  below  a  line  that 
would  be  parallel  with  the  center  of  the  screen,  because  at  best, 
an  extreme  short  focus  lens  requires  the  greatest  possible  care  in 
focusing  and  when  located  at  a  considerable  distance  above  or  below 
a  line  that  would  be  parallel  with  the  center  of  the  screen,  it  will  not 
be  practicable  to  get  a  sharp  focus  on  all  parts  of  the  picture. 


177 


102 


THE  MOTION  PICTURE 


To  Attach  the  Auxiliary  Front  Intermittent  Shutter  No.  3.  The 
auxiliary  front  intermittent  shutter  No.  3  is  used  in  front  of  the  lens. 
It  is  mounted  on  a  front  plate,  which  is  to  be  used  in  place  of  the 
regular  front  plate  that  comes  with  the  Motiograph  Model  No.  lA. 
On  the  shutter  shaft  is  a  beveled  pinion  and  for  connection  with 
this  pinion  is  a  second  beveled  pinion,  which  is  furnished  with  the 
shutter  and  front  plate.  This  second  beveled  pinion  is  to  be  attached 
to  the  shutter  drive  shaft  on  the  inside  of  the  mechanism,  by  first 
removing  the  larger  beveled  gear  that  is  attached  to  the  shutter 
drive  shaft.  These  beveled  gears  are  held  on  the  shutter  drive  shaft 
by  a  single  screw.  There  is  a  steel  plate  attached  to  the  center  of  the 
gear,  on  which  there  is  a  tongue  which  engages  with  a  groove  of  the 
same  size  in  the  shutter  drive  shaft.  Care  should  be  exercised  that 
the  tongue  is  properly  engaged  with  the  groove  in  the  shaft  before 


Fig.  60  Fig.  61 

Before  the  Lens  Shutter  in  Two  Positions  of  Adjustment 

tightening  the  screw.     When  using  the  front  shutter,  the  wings  of 
the  regular  cone  shutters,  No.  ]  and  No.  2,  should  be  removed. 

To  Set  the  JSIo.  3  Shutter.  Place  the  shutter  on  the  shutter  shaft, 
as  shown  in  Fig  55.  It  is  held  in  place  on  the  shaft  by  a  thumb 
nut  on  the  end  of  the  hub.  The  shutter  consists  of  three  wings,  one  of 
which  is  larger  than  the  other  two.  The  large  wing  is  intended  to 
cut  off  the  light  while  the  film  is  in  motion  and  the  other  two  serve 
as  interrupters  for  the  reduction  of  flicker.  To  set  the  shutter  in 
time  with  the  intermittent  film  sprocket,  loosen  the  thumb  nut  on 
the  hul)  of  the  shutter,  take  hold  of  the  balance  wheel  and  turn  the 
mechanism  very  slowly  in  the  same  direction  as  when  in  operation 
until  the  intermittent  sprocket  begins  to  move.  Set  the  top  edge 
of  the  large  wing  so  it  is  about  |  of  an  inch  above  the  center  of  the 


178 


MOTION  HEAD 


103 


lens,  Figs.  60  and  61.  Now  turn  the  balance  wheel  until  the  inter- 
mittent sprocket  stops,  then  see  that  tlie  lower  edge  of  the  large  wing 
of  the  shutter  is  about  \  of  an  inch  above  the  center  of  the  lens. 
The  shutter  should  be  set  as  far  back  on  the  shaft  as  is  practicable, 
that  is,  not  to  exceed  about  |  inch  from  the  front  of  the  lens  mount. 
When  properly  located  tighten  the  thumb  nut  on  the  shutter  hub. 
\Mien  long  focus  lenses  are  to  be  used,  the  shutter  may  be  reversed 
on  the  shaft,  that  is,  the  hub  and  thumb  nut  placed  at  the  rear. 
This  will  make  it  possible  to  set  the  shutter  well  to  the  front,  so  as  to 
pass  in  front  of  a  long  focus  lens. 

\^^len  using  alternating  current  of  60  cycles,  two  interrupters 
may  be  objectionable,  owing  to  the  fact  that  at  times  the  alternation 
of  the  current  is  liable  to  run  synchronously  with  the  interrupters 
in  the  shutter  in  such  a  way  as  to  very  largely  cut  down  the  illumina- 
tion. Wliere  this  condition  exists,  the  only  remedy  is  to  use  a  shutter 
having  but  one  interrupter. 

Index  of  Parts  for  the  Mechanism  of  the  No.  1A  Motiograph  Model 
1910,  Figs.  62  to  67  Inclusive 


lA  Main  frame  of  mechanism 

2A  Base 

3A  Gear  cover 

SiA  Gear  cover  for  motor  pulley 
and  idler 

4A  Bridge 

05A  Framing  device  (vertical  part) 

06  Framing    device    (horizontal 
part) 

7A  Upper  reel  arm — casting  only 

8  Upper  reel  arm  cap 

9A  Lower  reel  arm 

10  Arm  idler  tension 

11 A  Framing  lever 

12A  Main  clamp  thumb  wheel  and 

screw 

13A  Crank  without  handle 

013 A  Crank  handle  complete 

14  Balance  wheel 

15 A  Main  gear 


16A 


17A 
18A 


19 
20 
21 
22 
23 
24 

25 
26 

028 

29 
30 


Gear     and     pinion     between 
crank    shaft    and    balance 
wheel  pinion 
Gear  on  lower  sprocket  shaft 
Gear  between  balance  wheel 
shaft    and    lower    sprocket 
shaft 
Governor  crank  complete 
Small  belt  pulley  and  screw 
Large  belt  pulley  and  screw 
Lens  mount  ring 
Intermittent  roller  bracket 
Roller  bracket,  top,  with  ar- 
bors 
Roller  bracket,  bottom 
Spider  for  fireproof  magazine 
Bushing    for    intermittent 

sprocket  arbor 
Magazine  latch,  large  piece 
Magazine  latch,  small  piece 


17Q 


104 


THE  MOTION  PICTURE 


Fig.  62.     Motiograph  Par  3 


180 


MOTION  HEAD 


105 


pinion, 


pinion, 


31-32    Magazine  hinge 
33         Fire  trap,  casting  only 
33ct     Fire  trap,  complete  with  rol- 
lers 
37         Lens  arm  bracket 
38A      Shutter    arbor    and 

solid 
39A      Shutter     arbor    and 

main,  hollow 
40 A      Governor  drive  shaft 
41 A      Shutter  drive  shaft  screw 
42 A      Bushing   for    governor    drive 
43  A      Screw      for     intermittent 

sprocket 
44A      Screw    for    gear     on     upper 

sprocket  arbor 
45A      Bevel  gear  on  shutter  drive 

shaft 
46A      Bevel  gear  on  shutter  shaft 
47A      Intermediate  pinions  in  gear 

case 
48A      Screw    for    clamping    shutter 

wing 
50A      Crank  arbor  with  pin 
51A      Upper  sprocket  arbor 
52A      Lower  sprocket  arbor 

055  Ball  arbor 

056  Knuckle  joint  socket  on  Ge- 

neva arbor 

57  Reel  arm  socket  arbor 

58  Reel  arm  vertical  arbor 
59A      Reel  arbor,  upper 

60A      Reel  arbor,  lower 

61A      Balance     wheel     arbor     and 

socket 
62A      Balance  pinion  and  sleeve 

63  Upper  fire  shield 

64  Lower  fire  shield 

65  Governor  arbor 
65G.C.  Governor  complete 

69A      Bushing     for     shutter     drive 
arbor 


71  Framing  device  guide  rod 

72  Framing  device  slide  rod  and 

head 

74  Framing  lever  joint  screw 

75  Framing  lever  handle 

76  Framing  lever  fulcrum  screw 

77  Intermittent     roller     bracket 

joint  pin 
BOA      Bushing  for  gear  case  (rear) 
83         Governor  crank  arbor 
84A      Gear  on  governor  drive  shaft 

085  Bevel  gear  on  crank  arbor 

86  Bevel   pinion  on    upper    reel 

arm  arbor 
86^       Bevel  pinion  on  rewind  socket 
arbor 

87  Gear  on  upper  sprocket  arbor 
87^       Intermediate    gears,    small 

89  Bevel  gear  on  reel  arm  vertical 

arbor 

90  Gear  on  governor  arbor,  and 

hub 

91  Stereopticon  slide  rod 

91|       Stereopticon   slide   rod,    nut, 

and  washer 
92A      Screw  to  locate  gear  case 

93  A      Screw  to  retain  gear  case 

94  Push  rod  for  reel  arm 

95  Locking  pin  for  rewind  shift 
96 A      Film  tension  jaws,  each 
97A      Heat    arrester    gate 

99A      Thumb  screw  for  front  plate 

0100  Geneva  driver  and  arbor,  com- 

plete 

0101  Intermittent    sprocket    arbor 

and  star 

102  Screw  for  eccentric  bushing, 

framing  device 
103A    Screw  to  retain  shutter  drive 

bushing 
105A    Cap  for  hole  in  foot  of  main 

frame 


181 


THE  MOTION  PICTURE 

S6  >^  .eso 


38  A -^   ,80  A 


Fig.  63.     Motiograph  Parts 


\80A 


VSJA 


182 


MOTION  HEAD 


107 


106 

Sprocket,  upper  or  lower 

167A 

Connecting    bar   for   framing 

0107 

Intermittent  sprocket 

device 

108 

Film  roils 

168 

Rack  for  fire  shutters 

109 

Idler  pulley 

169 

Governor   strips,    each 

110 

Roller     guide     on     governor 

170  A 

Shutter  wing  (outer)  with  col- 

shaft 

let  and  screws 

111 

Governor  balls 

171A 

Shutter  wing  (inner)  with  col- 

112 

Oil  cup 

let  and  screws 

114A 

Gear  casing  for  shutter,  com- 

172- 

Front  plate 

plete  with  gears 

174  A 

Film  tension  spring 

116 

Roller,  top  of  door  (2  rolls  and 

175 

Governor   springs 

shaft) 

170 

Collar  on  reel  arm  vertical  arbor 

117A 

Locating    plunger    for    crank 

178 

Large    liushing    vertical    reel 

handle 

arbor 

118A 

Spring  for  locating  plunger 

181 

Bushing    for    balance    wheel 

119 

Center    pin    in    hinge   of   fire 

arbor,  small 

magazine 

182 

Bushing    for    balance    wheel 

120A 

Side  plate 

arbor,  large 

123 

Collar  on  door  latch  rod 

183 

Small    bushing   for   intermit- 

125 

Door  latch  rod 

tent  sprocket  shaft 

126 

Door  roller  pin 

0184 

Eccentric  bushing  for  framing 

127 

Ball  screw  and  door  hinge 

device 

128 

Screw    for    upper    and    lower 

193  A 

Bushing  in  bridge  for  govern- 

reel arm 

or  shaft 

129 

Screws  for  gear  and  idler 

194 

Bushing  in  frame  for  governor 

133 

Pin  in  governor  arbor 

shaft 

135 

Pin  for  motor  drive 

198 

Bushings  in  reel  arm  (small) 

0136 

Pin  in  Geneva  driver 

200 

Screw  in  governor  crank 

146 

Pin  reel  arm  vertical  arbor 

202 

Locating   screw   for   idler 

148 

Pin  in  gear  on  governor  arbor 

bracket  spring 

154 

Screw  in  crank 

203 

Screw  for  Nos.  23,  24,  25 

155 

Screw  in  handle  of  crank 

204 

Screws   for   sprockets,    upper 

156 

Adjusting  screw   on   take-up 

and  lower 

idler 

205 

Screw  for  balance  wheel 

157 

Check  nut  on  take-up  idler 

200A 

Screws  for  shutter  collet 

158 

Pin  in  vertical  reel  arbor  gear 

207 

Screws  for  upper  reel  arm  cap 

160  A 

Door  plate 

208 

Locating  screw  for  front  plate 

162  A 

A  perture   plate 

209 

Screws  to  fasten  magazines  to 

163 

Brass  shutter  and  pinion 

spiders 

164A 

Heat  arrester 

210 

Screws  for  spring  on  framing 

165 

Stripper  plate 

device 

183 


108 


THE  MOTION  PICTURE 


Fig.  04.     Motiograpli  Parts 


184 


MOTION  HEAD 


109 


211 
213 

214 

215 


Screws  for  stripper  plate 


224A      Screws  for  bridge 


216 

217 
218 
219 


Screws     for     small     bushing,       225 
framing   device  227 

Screws  for  large    bushing, 

framing  device  228 

Screws  for  framing  device  cap 


Screws  for  bushing  in  bridge 
Locating  screw  for  idler   ten- 
sion arm 
Screw  for  bushing  in  governor 
shaft 


Fig.  65.     Motiograph  Framing  Device  Parts  Assembled 


Screws  for  friction  on  vertical  230 

rod 

Screws  for  aperture   plate  231 

Screws  for  fire  shields  232 

Screws  for  studs  on  door  233 


Screw    in    reel    arbor    bevel 

pinion 
Upper  screw  for  gear  cover 
Left  side  screw  for  gear  cover 
Right  side  screw  for  gear  cover 


Fig.  66.     Parts  for  No.  2  Motiograph  Mechanism 


220  Screws  for  door  latch 

221  Screws  for  tension  springs 

222  Screws  for  stop  on  door 

223  Screws  for  roller  arbors 


235         Screw  for  holding  bushing  in 

frame 
237         Screw  for  attaching  magazine 

to  reel  arm 


185 


no 


THE  MOTION  PICTURE 


238 

Magazine  body  and  cover 

273 

241 

Check  nut  on  roller  bracket 

244 

Screw    for     locating     crank- 
handle 

274 

245 

Set  screw   in   socket   arbor 

275 

246 

Screw  in  roller  bracket 

248 

Safety  cap  for  crank  arbor 

276 

249 

Screw  to  hold  roller  bracket 

in  place 

277 

251 

Roller  for  fire  trap,  plain 

284 

252 

Roller  for  fire  trap,  with  flange 

285 

253 

Pins  for  roller  arbor 

286 

254 

Tension  plunger  in  fire  trap 

287 

255 

Screws  to  hold  traps  to  maga- 

288 

zines 

289 

256 

Screws  for  fire  trap 

257 

Screws  for  jiut  on  reel  arbor 

290 

258 

Spring  for  pressure  rollers  in 

fire  trap 

291 

258i 

Spring  for  gate  latch 

259 

Set  screw  to  bind  bushing  in 
reel  arm 

292 

261 

Wood  handle  for  crank 

293 

262 

Screws  to  check  guide  rod 

263 

Screws  for  small    belt    pulley 

294 

265 

Screws     for     roller     bracket 

295 

springs 

296 

267 

Screws    for    framing    device 

297 

bushing 

298 

268 

Screws  in  magazine  latch 

299 

Springs    for    framing    device 

(2  pieces) 
Springs  for  roller  bracket   (3 

pieces) 
Springs    for    front    plate     (2 

pieces) 
Set  screw  for  large  bushing  on 

balance  arbor 
Take-up  belt 
Spring  for  push  rod 
Balance  arbor  screw 
Motor  drive  arbor 
Shutter  drive  arbor  and  pinion 
Gear  case 
Screws   for   bushing   in   gear 

cases 
Arbors  for  intermediate  gears 

in  gear  case 
Screw  in  gearon  lower  sprocket 

arbor 
Adjusting  screw  for  eccentric 

bushing  in  framing  device 
Screw     for     socket     Geneva 

arbor 
Screw  for  upper  fire  shield 
Latch  pin  for  side  plate 
Nut  for  latch  pin 
Spring  for  latch  pin 
Screws  for  side  plate 
Bushing  for  gear  case  (front) 


MOTIOGRAPH  No.  lA  ARC  LAMP 


MG  1     Burner  slide 

MG  1}  Machine  screws 

MG  3     Main  body 

MG  3  J   Main  body  stud  to  hold  upper 

castings 
MG  4     Lower  horizontal  casting 
MG  4i  Stud 


MG  5     Upper  horizontal  casting 
MG  5+  Upper  horizontal  casting  stud 
MG  9     Carbon  clamp,  complete;  long 

(1) 
MGIO     Carbon  clamp,  short 
MGll     Upper  carbon  clamp  bracket 
MG12     Upper  rack  bracket 


MG  4i  Lower  horizontal  casting  stud      ]\IG16     Lower  carbon  clamp  bracket 


MG  4}  Roller 


MG17     Lower  rack  bracket 


I 


186 


5  ? 

03    _■ 


I 


<:  &q 
►J 

o 

O    S 


o 


MOTION  HEAD 


111 


MG18     Upper  rack  MG39i 

MG19     Lower  rack 

MG20     Screw    for    lower    horizontal  MG40 

casting  MG40i 

MG22     Rack  plate  MG40| 

MG22^  Screws  MG41 
MG23     Rack  pinion  and  arbor 

Rack  pinion  ball,  joint  and  pin  MG46 

Rack  pinion  ball  screw 

Shaft  to  operate  racks,  com-  MG465 

plete  -  MG47 


MG24 
MG24 
MG25 


Swivel  screw  for  up  and  down 
adjustment 

Socket 

Ball  joint  screw 

Pin 

Shaft  for  up  and  down  ad- 
justment, complete 

Wood  handle  on  up  and  down 
adjustment 

Screw  for   wood   handle 

Plate  on  lower  carbon  clamp 


Fig.   67.     Parts  for  Motiograph  No.  lA  Arc  Lamp 

MG26    Wood  handle  for  shaft  racks  MG39     Swivel  for  up  and  down  ad- 
MG26i  Screws  for  wood  handle,  rack  justment 

shaft  MG47j  Screws  for  plate 

MG30     Shaft    for    side    adjustment,  MG48     Wing  nuts  for  carbon  clamps 

complete  (2)^X24 

MG31     Wood  handle,  side  adjustment  MG49     Machine  screws  to  hold  short 
MG3U  Screw  for  wood  handle  clamps  (2)  10  X24 

MG32     Swivel  collar  for  side  adjust-  MG50     Washers     for     short     carbon 

ment  clamps 

MG33     Screw  to  hold  swivel  collar  MG53     Machine  screws  to  hold  long 
MG34     Washer    on    side    adjustment  clamp  to  bracket  (4)  |  X24 

shaft  MG54     Thumb  screws  to  hold  wire, 
MG38     Screw  for  up  and   down  ad-  (2) 

justment  MG55     Washers  for  Xo.  54   (4) 


187 


112 


THE  MOTION  PICTURE 


MG56     Machine      screws      to      hold       MG64 
brackets 

MG.57     Machine  screws  to  hold  upper 
bracket  on  rack,  (1)  10  X24 

MG58     Machine  screws  to  hold  upper 
rack  on  bracket  (1)  8X32 

MG59     Machine  screws  to  hold  lower 
rack  on  bracket  (2)  8X32 

MG62     Mica  insulators — flat — set 

MG63     Mica   insulators  round  bush- 
ing 


Mica  insulators   round   wash- 
ers 

Iron  washers  for  M.G.  r)G 

Main  body  No.  2  and  stud  (for 
use  on  Xo.  2  Motio) 

Shaft  for  Xo.  2  up  and  down 
adjustment,    complete    (for 
use  on  X"o.  2  Motio) 
MG85     Rack  body  (new  style) 
MGS6     Bracket  for  rack  body  (new 
style) 


MG65 
MG75 

MG80 


UPPER  CARBON  ADJUSTMENT  FIXTURE 


MG91     Rack  bracket  for  adjustment 

fixture 
MG92     Adjustment   bracket  for  car- 

l)on  clamp 
MG93     Support  bolt 
MG94     Adjustment  screvv 
MG95     Adjustment  handle 
MG96     Clamp  bolt 


MG97     Collar  for  adjustment  screw 
MG98     Stock  washer  rV  X/s  inch 
MG99     Stock     screw  —  round    head, 

8-32  X 1  inch  • 
MGIOO  Pin  for  collar  for  adjustment 

screw /aXi  inch 
MGlOl  Headless    screw    for    adjust- 
ment   thumb   nut 


UPPER  UNIVERSAL  CARBON  CLAMP 


MGllO  Bracket  (long) 
MGlll  Clamp  screw  for  bracket 
MG112  Locating  screw  for  bracket 
MG113  Swivel  for  bracket 
MG114  Clamp  screws  for  swivel 


MG115  Washers  for  clamp  screws  for 

swivel 
MG116  Carbon  holder 
MGl  17  Wing  nut  for  carbon  holder 


LOWER  UNIVERSAL  CARBON  CLAMP 


MG118  Bracket  (long) 
MG119  Clamp  screw  for  l^racket 
MG120  Locating  screw  for  bracket 
MG121  Swivel  for  bracket 
MG122  Clamp  screw  for  swivel 
MG123  Washers  for  clamp  screws  for 
swivel 


:MGr24  Carbon  holder 
MG125  Wing  nut  for  carbon  holder 
MGl 26  Stop  plate  on  carbon  holder 
MGl 27  Screws  for  stop   plate 


188 


MOTION  HEAD 


113 


POWER'S  NO.  5  CAMERAQRAPH 

The  Power's  No.  5  caraeragraph  is  a  projecting  machine  which 
has  been  well  known  for  several  years.    The  right  side,  or  crank  side, 


Fig.  6S.     Crank  Sick;  of  Power's  No.  5  Cameragraph 

of  the  motion-head  mechanism  of  the  No.  5  model  is  shown  in  Fig. 
68,  while  the  reverse,  or  left  side,  is  shown  in  Fig.  69.     In  the  illiis- 


189 


114 


THE  MOTION  PICTURE 


trations,  the  motion  head  is  equipped  with  an  upper  reel  hanger, 
holdino-  an  open  reel  for  the  feed  reel  of  film,  instead  of  the  iron  fire- 


Fig    69.     Left  Side  of  Power's  No   6  Cameragraph 

proof  magazine.     By  the  turning  of  two  thumb  screws,  the  upper 
reel  hanger  may  be  lifted  off  and  the  fireproof  magazine  hung  in 


190 


r 

I 


MOTION  HEAD  115 

its  place.  This  furnishes  a  convenience  in  packing,  and  in  working 
about  the  motion  head  to  clean  it  up  before  beginning  the  evening's 
run  of  the  show. 

The  intermittent  mechanism  is  the  standard  three-sprocket 
type,  upper  steady  feed,  intermittent  sprocket  at  the  film  gate,  and 
lower  steady  feed  below.  The  intermittent  (in  the  No.  5  mechanism) 
is  driven  by  the  Geneva  form  of  drive,  kept  in  balance  by  a  heavy 
fly  wheel  mounted  directly  upon  the  pin  shaft  of  the  intermittent 
mechanism.  The  four-slot  Geneva  star  and  one-pin  cam  is  used, 
and  the  mechanism  is  timed  to  about  j  motion  and  f  rest  for  each 
picture. 

The  shutter  of  the  No,  5  model  is  within  the  motion  head, 
mounted  very  close  to  the  film  window.  It  projects  near  the  crank 
handle  of  the  motion  head,  and  is  covered  by  the  curved  shield  seen 
near  the  handle  in  Fig.  68.  The  shutter  is  of  the  so-called  "balanced" 
or  multiple  wing  t^^pe,  two  wings  being  used,  the  broader  one  cover- 
ing the  aperture  during  the  shift  of  the  film  and  the  narrower  one 
being  introduced  to  reduce  the  flicker. 

The  framing  mechanism  is  a  sliding  carriage  on  the  main  body 
of  the  motion  head;  it  carries  the  intermittent  sprocket,  the  pin 
wheel,  and  the  star  wheel,  and  it  is  shifted  by  a  short  framing  lever 
having  a  toggle  joint  with  the  carriage. 

An  ingenious  arrangement  of  gearing  is  pi*ovidetI  by  which 
a  constant  meshed  gear  connection  is  maintained  between  the  crank 
shaft — which  is  mounted  rigidly  in  the  main  body  of  the  motion 
head — and  the  Geneva  movement,  which  is  carried  movably  by  the 
framing  carriage.  A  spur  gear  on  the  main  body  and  a  spur  gear 
on  the  pin-wheel  shaft  of  the  framing  carriage  have  an  idler  spur 
wheel  between  them,  the  idler  being  hung  upon  a  pair  of  movable 
arms  which  keep  it  at  all  times  meshed  with  both  of  its  meshing 
gears  in  the  train. 

The  presser  rollers  by  which  the  film  is  kept  in  engagement 
with  the  feed  sprockets  are  all  mounted  in  pivoted  brackets,  con- 
trolled by  springs,  and  are  provided  with  set  screws  by  which  the 
rollers  may  be  adjusted  to  the  sprockets  to  secure  proper  control  of 
the  film. 

The  aperture  plate  is  provided  with  hardened  steel  guide  strips 
on  its  face  for  guiding  the  film.     On  the  film  gate,  in  front  of  the 


191 


116 


THE  MOTION  PICTURE 


film  window,  and  on  the  lamp-house  side,  is  a  heavy  plate  called  a 
"coohng"  plate,  apparently  having  no  function  in  the  operation  of 
the  machine,  but  its  purpose  is  to  prevent  the  rays  of  the  lamp  from 
shining  directly  upon  the  film  gate  and  heating  it  to  a  high  degree 
which  would  endanger  the  film. 

The  upper  reel  hanger  is  provided  with  a  rewind  handle,  hence 
it  is  not  necessary  to  detach  the  main  drive  handle  or  move  it  to  a 
new  position  to  rewind  the  film.    The  rewind  handle  does  not  engage 


Fig.   70      Cameragraph  Lamp  House,  No.  5  Model 

the  feed  reel  until  pushed  in  upon  its  shaft,  so  it  does  not  interfere 
with  the  turning  of  the  feed  reel  during  the  unwinding  of  the  film 
for  projection. 

The  lamp  house  slides  u\vni  a  double  rod  track  to  pass  from 
the  motion  head  to  the  stereo  lens,  or  vice  versa,  and  this  double-rod 
cross  track  in  turn  slides  u])on  a  pair  of  rails  or  rods  upon  the  pro- 
jection table  which  enables  the  lamp  house  to  be  placed  at  any 
desired  distance  from  the  motion  head  and  stereo  lens,  thus  afford- 
ing every  facility  for  the  projection  operator  to  get  his  condensers 
and  his  lens  into  proper  focal  relation  with  each  other.  The  lamp 
house  and  its  double  arrangement  of  cross  tracks  is  shown  in  Fig.  70. 


192 


MOTION  HEAD 


117 


The  lamp  is  a  two-knob  lamp,  eas}-  for  the  beginner  to  control 
during  the  projection  of  the  pictures,  because  he  is  not  likely  to  turn 
the  wrong  knob  and  throw  out  a  carefully  adjusted  screen  illumina- 
tion. The  lamp  is  shown  in  Fig.  71.  The  larger  knob  is  the  feed 
knob,  by  which  the  arc  is  struck  and  the  carbons  are  fed  down  as 
they  burn  away  during  projection.  The  smaller  knob  is  the  tilting 
knob,  by  which  the  lamp  frame  of  the  lamp,  including  the  feed  rods, 
carbon  clamps,  and  carbons,  is  tilted  up  or  down,  according  as  the 


Fig.   71.     Cameragraph  Lamp,  No.  .5  Model 

knob  is  turned,  to  bring  the  arc  into  proper  center  with  the  con- 
densers. The  proper  distance  of  the  arc  from  the  condensers  and 
the  proper  transverse  or  side  adjustment  of  the  lamp  is  made  inside 
the  lamp  house,  through  the  door.  The  height  is  made  by  the  slid- 
ing block  and  set  screw  which  clamps  it  to  the  vertical  rod  of  Fig. 
71,  upon  which  the  lamp  frame  is  mounted.  The  distance  from  the 
condensers  forward  or  back  in  the  lamp  house  is  made  by  mo\ing 
the  base  of  the  vertical  rod,  in  the  house,  but  in  some  of  these  lamps 
there  is  a  third  knob  projecting  at  the  very  bottom  of  the  lamp  house 
at  the  back,  and  the  lamp  may  be  slid  toward  or  from  the  condensers 
by  turning  this  extra  knob,  which  is  so  low  that  it  is  not  likely  to  be 


193 


118 


THE  MOTION  PICTURE 


touched  bv  accident  during  projection.  The  design  of  the  Power's 
lamp  and  lamp  house  is  such  as  to  avoid  accidental  moving  of  parts 
which  should  be  left  alone  during  projection. 

The  top  of  the  Power's  lamp  house  is  liinged,  and  may  be  swung 
upward  to  afford  convenience  in  setting  the  carbons,  the  oper- 
ator passing  one  hand  through  the  top  of  the  lamp  house  and  the 
other  through  the  door. 

The  lamp  house  also  has  the  douser  shut- 
ter between  the  condenser  and  the  lantern 
slide,  instead  of  at  the  end  of  the  condenser 
hood,  thereby  protecting  the  slide  when  not 
being  projected. 

The  fireproof  magazines  for  feed  and  take- 
up  reels  are  provided  with  a  special  type  of 
roller  fire  trap,  shown  in  Fig.  72.  It  \nll  be 
noticed  that  one  of  the  rollers  of  the  fire 
trap  has  its  shaft  projecting  at  both  ends.  In 
feeding  the  film  end  through  the  trap,  the 
ends  of  this  roller  are  caught  with  two  fingers 
and  the  roller  is  slid  back  in  its  slots  to  per- 
mit the  end  of  the  film  to  pass. 

The  Power's  machines  are  equipped  with 
two  styles  of  fire  shutters.  Style  A  is  shown 
in  Fig.  73.  It  is  operated  by  an  inward 
movement  of  the  driving  crank  upon  the  shaft.  The  crank  is  set 
upon  the  shaft  with  a  cam  slot  and  a  pin  and  spring,  so  that  when  the 
power  is  appHed  to  turn  it,  it  automatically  moves  inwardly  to  open 
the  shutter.  Style  B  is  shown  in  Fig.  74.  This  shutter  requires  that 
the  mi^'hanism  have  a  certain  speed  of  revolution  before  the  shutter 
will  operate  to  open  the  film  window  to  the  light  of  the  arc  lamp, 
and  it  is  operated  by  a  centrifugal  wheel  geared  to  the  film  dri\ang 
mechanism  of  the  motion  head.  Upper  and  lower  film  shields  are 
shown  in  Fig.  74.  The  lower  shield  is  hinged  at  the  bottom,  to  per- 
mit the  operator  to  get  at  the  mechanism  for  threading  up  the  film. 
Figs.  75  and  76  give  illustrations  of  such  parts  of  the  Power's 
No.  5  Cameragraph  as  are  likely  to  be  needed  for  repairs,  and  iden- 
tify them  by  number.  In  ordering  a  repair  part,  both  name  and 
number  should  be  ijiven. 


Fig.  72.     Cameragraph  Film 
Outlet  and  Fire  Trap 


194 


MOTION  HEAD 


119 


Fig.   73.     Cameragraph  Safety  Shutters,  Style  A 


I'ig.  74.     Cameragraph  Safety  Shutters,  Style  B 


195 


120 


THE  MOTION  PICTURE 


1 

1 

r 

n 

Ik 

'i\\ 

ii 

\ 

5/ 

rs  74   rs 

Fig.  75.     Parts  of  No.  5  Camcragraph 


196 


?l 


MOTION  HEAD 


121 


INDEX  OF  PARTS 


10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 

23 
24 
25 
26 
27 
28 
29 
30 
31 
32 
33 
34 
35 
36 
37 


Reel  hanger  frame  38 

Machine  top  frame  39 

Machine  body  frame  40 

Machine  framing  carriage  41 

Machine  base  casting  42 

Take-up  feed  frame  43 

Machine  crank  44 

Fly  wheel  45 
Stereo     bracket     with     thumb         46 

screw  47 

Stereo  bracket  holder  48 

Crank  shaft  bearing  49 

Framing  device  lever  socket  50 

Framing  device  clamp  51 

Framing  device  link  for  lever  52 

Top  feed  smng  bracket  53 

Cooling  plate  54 

Toggle  joint,  large  arm  55 

Toggle  joint,  small  arm  56 

Stereo  flange  collar  casting  57 

Take-up  feed  roller  bracket  58 

Intermittent  roller  bracket  59 

Steel  thumt)  screw,  nickeled  60 

plain  61 

Reel  hanger  shaft  62 
Reel  hanger  gear 

Reel  hanger  crank  63 

Reel  hanger  crank  handle  64 

Heavy  feed  sprocket  65 

Feed  sprocket  shaft  66 

Feed  sprocket  gear  67 

Wing  nut  68 

Set  collar  69 
Reel  hanger  spindle 

Reel  hanger  spindle  gear  70 

Shutter  shield  71 

Toggle  joint  set  collar  72 

Aperture  plate  73 

Toggle  joint  spindle  74 


Toggle  joint  gears 

Intermittent  bracket  spindle 

Intermittent  bracket  spring 

Intermittent  bracket  roller 

Intermittent  roller  set  collar 

Upper  feed  gear  and  spindle 

Framing  lever 

Crank  shaft  gear 

Steel  peeler 

Apron 

Take-up  feed  driving  pulley 

Geneva  or  star  wheel 

Eccentric  bushing 

Intermittent  sprocket,  light 

Intermittent  shaft  or  spindle 

Eccentric  bushing  (end  view) 

Plain  bushing 

Shutter,  revolving 

Shutter  gear,  each 

Shutter  set  collar 

Shutter  spindle 

Top  feed  bracket  spring 

Front  plate 

Base  board  for  mechanism 

Take-up     feed     roller     bracket 

spring 
Gears  for  take-up  feel 
Hea^'y  sprocket  for  take-up  feed 
Take-up  feed  spindle 
Film  tension  springs 
Latch  for  door 
Plate  door  or  gate 
Guide  rollers,    spindle    bushings 

and  springs 
Pin  wheel  or  Geneva  driver 
Main  spindle 
Steel  pinion 
Machine  frame  support 
Maciiine  frame  support 


197 


122 


THE  MOTION  PICTURE 


Fig.  76.     Parts  of  No.  5  Cameragraph 


108 


MOTION  HEAD 


123 


75 

Stereo  lens  bracket  rod 

125 

Coil  for  120  volt  circular  rheo- 

100 

Arc  lamp  base,  complete 

stat 

101 

Arc  lamp  base  casting,  with  post 

126 

Coil  for  25  amp.  rheostat 

102 

Arc  lamp  base  adjusting  screws 

127 

Coil  for  240  volt  circular  rheo- 

and handle 

stat 

103 

Dowser,  complete 

128 

Rheostat  crank,  complete 

104 

Dowser  shield 

129 

Rheostat  crank  casting 

105 

Dowser  handle 

130 

Rheostat  crank  handle 

106 

Dowser  handle  casting 

131 

Rheostat  crank  contact  spring, 

107 

Dowser  handle  knob 

small 

108 

Funnel  support 

132 

Rheostat  crank  contact    spring. 

109 

Condenser  mount  bracket  cast- 

large 

ing,  lower 

133 

Arc  lamp  rack  handle 

110 

Condenser  mount  bracket  cast- 

134 

Arc  lamp  carbon  holder,   com- 

ing, upper 

plete 

111 

Rheostat  binding  post  casting 

135 

Arc  lamp  carbon  holder  jaw 

112 

Lamp  house  sliding,  sleeve 

136 

Arc  lamp  carbon  holder  lip 

113 

Lamp  house  sliding  rod,  longi- 

137 

Arc  lamp  carbon  holder  knuckle 

tudinal 

lower 

114 

Lamp  house  sliding  rod,  cross- 

137A  Large    plain   thumb    screw   for 

wise 

knuckle       ' 

115 

Lamp  house  sliding  rod,    exten- 

138 

Arc  lamp  carbon  holder  knuckle 

sion 

upper 

116 

Lamp  house  sliding  rod,    holder 

138A  Small    plain    thumb    screw    for 

bracket 

lower  knuckle 

117 

Lamp  house  stop  with    thumb 

139 

Arc  lamp  carbon  holder  knuckle 

screw 

bracket 

118 

Binding  post  for  circular  rheo- 

140 

Xo  longer  used 

stat 

141 

Arc  lamp  supporting  Iiracket 

119 

Binding  post  for  25  amp.  rheo- 

142 

Arc    lamp    supporting    bracket 

stat 

thumb  screw 

120 

Coil  terminal  for  25  amp.    rheo- 

143 

Arc  lamp  adjustment  rack  guide 

stat 

casting 

121 

Coil  terminal  for  25  amp.  rheo- 

144 

Arc  lamp  adjustment  rack 

stat  (end) 

handle,  small 

122 

Coil  terminal  for  circular  rheo- 

145 

Arc  lamp  adjustment  rack 

stat  (intermediate) 

146 

Arc  lamp  adjustment  rack  cast- 

123 

Jumper  spring  for  circular  rheo- 

ing pin 

stat  terminal 

147 

Arc  lamp  name  plate 

124 

Coil  terminal  for  circular  rheo- 

148 

Rheostat  (25  amp.)  adjustment 

stat  (double),  complete 

base,    complete 

199 


124 


THE  MOTION  PICTURE 


149  Rheostat  (25  amp.)  crank,  com- 

plete 

150  Center    post    of    25    amp.    adj. 

rheostat 

151  Stop  spindle  on  circular  rheostat 

152  Center  post  on  circular  rheostat 

153  Upper  magazine  spindle 

154  Lower  film  shield 

155  Lower  film  shield  hinge  spring 

156  Upper  film  shie!  1 

157  Machine    crank    for    style    "A" 

mechani.5m 

158  Crank   spring    with    l)utton   for 

style  "A"  mechanism 

159  "V"     spring     for     style      "A" 

mechanism 

1(30  Crank  shaft  for  style  "A"  shut- 
ter mechanism 

Ibl  Crank  .shaft  and  pinion  for  style 
"B"  shutter  mechanism 

162  Lever  for  style  "A"  shutter 

163  Lever  for  style  "B"  .shutter 

164  Lever    support    for    style    "B" 

shutter 

165  Friction  case  cover,  style  "B" 

shutter 
I  GO     Friction   case   cover,  style  "B" 
shutter 

167  Friction  shoe,  style  "B"  shutter 

168  Friction  weights,  style  "B"  shut- 

ter, each 

169  Crank    shaft    l^earing   for    style 

"A"  shutter 

170  C^ooling  plate  and  flap  complete 

for  automatic  shutters 


171  Rock  shaft  for  style  "B"  shutter 

172  Rock  shaft  for  style  "A"  shutter 

173  Left  bearing  for  shaft,  style  "B" 

shutter 

174  Right    Ijearing    for  .shaft,   style 

"3"  shutter 

175  Pivot  for  lever,  style  "A"  .shut- 

ter 

1 76  Ruby  glass  frame  for  lamp  house 

door 

177  Wooden   knol)   for   lamp  house 

door 

1 78  Catch  holder  for  lamp  house  door 

1 79  Catch  for  lamp  house  door 

180  Valve  for  upper  magazine 

181  Valve  for  lower  magazine 

182  Support  casting  for  lower  maga- 

zine 

183  Cross  casting  for  lower  magazine 

184  Reel  cotter 

185  Cross  casting   for   upper  maga- 

zine 

186  Lower  take-up  attachment 

187  Front  take-up  attachment 

188  Take-up  spindle 

189  Take-up  spindle   tension   spring 

190  Split  pulley  for  take-up  attach- 

ment 

191  Guide   roller   casting   for   lower 

take-up  attachment 

192  Guide  roller   for   lower  take-up 

attachment 


POWER'S  NO.  6  CAMERAQRAPH 

The  intermittent  movement  of  the  No.  G  model  Is  a  radieal 
departure  from  that  of  the  No.  5  model,  and  indeed  from  all  pre- 
viou.s  nittdels  of  intennittents.       It  ha.s  no  pin  wheel,  no  star  wheel, 


200 


MOTION  HEAD 


125 


no  Geneva.  It  is  not  a  beater,  dog,  nor  claw.  Neither  is  it  a  friction 
grip.  Two  parts  are  used,  similar  in  relation  to  the  cam  wheel  and 
star  of  the  Geneva,  but  rather  reversing  the  order,  since  the  pin 
wheel  is  the  intermittent.  The  driving  element  is  a  revolving  cam, 
substantially  diamond  shaped,  upon  the  face  of  a  heavy  steel  disk 
carrying  also  a  steadying  or  locking  band,  as  is  carried  by  the  pin  wheel 
of  a  Gene^•a.  The  driven  element  is  a  cross  upon  the  end  of  the  in- 
termittent shaft.  In  each  of  the  arms  of  the  cross  is  a  pin.  The  cam 
band  and  diamond  drive  block  upon  the  face  of  the  driving  disk  are 
shown  in  Fig.  77,  as  are  also  the  cross  and  pins,  separated  from  their 


Fig. 


Intermittent  Movement  Meelianism,  Power's  No.  6  Model 


driving  and  locking  elements.  The  position  of  the  pin  cross  is 
shown  in  dotted  lines  in  the  locking  band.  In  manufacture, 
the  cross  and  pins  are  cut  from  a  single  block  of  steel.  The  parts 
of  the  intermittent  movement  are  enclosed  in  an  oil-tight  casing, 
with  an  oil  feed  cup,  and  by  keeping  the  casing  properly  filled  with 
oil  a  practically  noiseless  movement  of  the  intermittent  drive  is 
assured,  Fig.  78. 

The  shutter  is  of  the  three-wing  type,  and  is  mounted  upon  a 
spindle  which  projects  forward  from  the  front  plate  of  the  motion 
head,  so  that  the  shutter  intersects  the  rays  of  light  in  front  of  the 
projection  lens.  The  shutter  is  adjustable  longitudinally  of  the 
spindle,  so  that  it  can  be  set  close  to  the  front  of  the  lens  whether  a 
long  or  short  focus  of  lens  is  used.  The  hub  of  the  shutter  con- 
sists of  an  inner  and  outer  sleeve;  the  inner  sleeve  is  directly  and 
permanently  attached  to  the  spindle,  and  the  outer  sleeve  is  adjustable 


201 


126 


THE  MOTION  PICTURE 


upon  the  inner  sleeve  to  permit  quick  and  accurate  setting  of  the 
shutter  with  relation  to  the  intermittent  movement.  The  mount- 
ino"s  of  the  shutter  spindle  are  such  that  when  the  shutter  is  detached 
for  packing  the  mechanism,  the  spindle  is  swung  down  into  close  con- 
tact with  the  front  of  the  motion  head,  where  it  will  be  protected  from 
injurv  in  shipment.  Owing  to  the  rapid  movement  of  the  film 
produced  by  the  new  intermittent  mechanism  (one-sixth  movement 
and  five-sixths  rest  for  each  picture  interval),  the  shutter  wings  may 
be  cut  narrower  than  in  most  shutters  of  the  three-wing  type,  thereby 
giving  the  screen  all  possible  advantage  of  the  lamp.  If  the  oper- 
ator does  not  try  to  burn  his  lamp  too  brightly  he  should  be  able  to 


Fig.   7S.     Complete  No.  G  Cameragraph  Intermittent  Mechanism   } 

get  his  flicker  well  down  toward  elimination  with  the  No,  6  model 
cameragraph,  but  if  he  tries  to  crowd  on  all  the  light  he  can  from  his 
lamp,  the  brighter  illumination  of  the  screen  by  the  narrower  .shutter 
blade  will  bring  back  some  of  the  flicker  which  the  rapid  film  shift 
endeavors  to  reduce.  The  shutter  gears  are  angle  gears  (not  bevel 
gears),  and  have  faces  f  of  an  inch  in  width,  thus  insuring  long 
service  without  perceptible  wear. 


202 


s  ^ 


hj  ■- 

P<  _ 

o  ■ 

O  ; 


o  : 

OS  i;- 

fc  ■- 

w  = 

^  ? 

W  -I 


o 

b 
< 

u 
M  : 

O  rt 
O^ 

2  -^  i 
«JJ  -  = 
H  -£- 

21-  = 

H  =  J 
D  -  5 
O  >-- 
w  -•"- 

W  r  J 
IZI  —  J 

«  "" 

o  =•- 

u.   -  — 


^  2 
o  - 

OS   g 


MOTION  HEAD 


127 


The  picture  is  framed  by  a  slight  vertical  movement  of  a  car- 
riage bearing  the  intermittent  sprocket,  and  the  framing  lever  is 
mounted  on  the  base  of  the  mechanism  or  machine  head,  where  it 


Fig.   79.     Power's  No. 6    Cameragraph 

can  be  readily  reached  with  the  left  hand  without  interfering  with 
the  operation  of  the  machine.  The  movement  of  the  framing  car- 
riage does  not  alter  the  relation  of  the  shutter  to  the  picture  gauge  or 
projection  aperture.     The  gearing  connection   to   the  framing  car- 


203 


128 


THE  MOTION  PICTURE 


riage  has  all  the  gears  arranged  in  a  straight  hne,  eHminating  a  toggle 
joint  and  toggle  joint  gears. 

The  film  feed  comprises  three  sprockets  in  accordance  with 
the  usual  American  practice.  The  top  feed  sprocket  and  the  bot- 
tom or  take-up  feed  sprocket  run  constantly,  and  the  middle  or  in- 
termittent sprocket  makes  a  complete  turn  in  four  successive  move- 
ments with  alternate  periods  of  rest,  which  are  four  times  as  long  as 
the  periods  of  movement.  All  the  sprockets  are  cut  from  specially 
selected  steel  to  insure  long  wear  and  accuracy  of  size  and  form. 


Fig.   SO.     Camerag  aph  No.  6  Lamp 


The  film  is  held  in  position  upon  the  top  feed  sprocket  by  means 
of  two  rollers,  one  a  flanged  guide  roller  turning  on  a  fixed  spindle, 
and  the  other  a  holding  roller  mounted  on  a  spring  pressed  bracket. 
The  latter  roller  rests  directly  over  the  top  feed  sprocket  when  in 
use  and  keeps  the  film  in  perfect  engagement  with  the  sprocket 
teeth. 

The  film  is  held  in  position  on  the  intermittent  sprocket  by 
means  of  a  roller  mounted  on  a  pivoted  bracket,  which  is  so  shaped 
that  it  serves  also  as  a  guide  for  the  film.  When  the  idler  roller  for  the 
intermittent  sprocket  is  in  service  it  lies  practically  under  the  inter- 


204 


MOTION  HEAD 


129 


mittent  spindle  and  insures  engagement  of  die  film  with  at  least  four 
teeth  on  each  hub  of  the  intermittent  sprocket. 

A  pair  of  idler  rollers  are  provided  to  keep  the  film  in  position 
upon  the  lower  or  take-up  feed  sprocket,  these  idlers  being  mounted 
in  a  frame  w4iich  is  arranged  to  rock  on  a  spindle  carried  by  a  spring 
pressed,  pivoted  bracket.  The  lower,  or  take-up,  feed  sprocket 
controls  the  rate  at  which  the  film  is  taken  up  in  the  lower  magazine, 
and  it  is  of  the  utmost  importance  that  "riding"  of  the  film  on  this 
sprocket  be  prevented.  This  is  completely  accomplished  by  means 
of  the  arrangement  of  idler  rollers. 


Fig.   81.      Power's  Rheostat 

To  prevent  wear  of  the  film  in  traveling  o\er  the  sprockets,  all 
the  idler  rollers  which  hold  it  in  position  thereon  are  so  supported 
that  no  pressure  of  the  film  against  the  sprockets  is  produced  by  the 
idler  rollers,  but  the  possibility  of  disengagement  of  the  film  with  the 
sprockets  is  completely  obviated. 

The  film  guides  and  friction  devices  are  arranged  to  make  the 
friction  of  the  film  through  the  motion  head  as  light  as  possible. 
At  the  top  of  the  gate  a  pair  of  hght  flanged  rollers  are  pro\ided 
through  which  the  film  tra\els  to  the  aperture  plate.  The  tension 
on  the  film  necessary  to  insure  steady  pictures  is  produced  between 
guide  rails  or  wear  strips  of  hard  steel  on  the  aperture  plate  and  a 


205 


130 


THE  MOTION  PICTURE 


pair  of  tension  springs  provided  with  half-round  hardened  steel 
tension  contact  shoes.  To  prevent  wear  on  the  film  in  passing  from 
the  intermittent  sprocket  a  steel  apron  with  polished  surface  is  pro- 
vided, over  which  the  film  travels  with  but  litde  friction.  The 
usual  safety  devices  of  upper  and  lower  film  magazines,  fire  shields, 

fire  traps  in  the  magazines,  film 
shields,  and  safety  shutter  are  used 
in  the  No.  6  model  and  are  similar 
to  those  described  in  the  No.  5 
Model  Cameragraph. 

The  lamp  house  of  the  No.  6 
model  has  its  four  adjustments  out- 
side of  the  house,  the  lamp  being 
mounted  upon  an  iron  frame  inside 
the  house,  and  being  accessible  from 
all  sides  by  reason  of  doors  in  both 
sides  of  the  house  and  a  swinging 
top  upon  the  house  as  well. 

The  No.  6  cameragraph  mechan- 
ism is  shown  in  Fig.  79,  and  the  No. 
6  cameragraph  lamp  in  Fig.  80. 
The  Power's  rheostat,  which  accom- 
panies the  Power's  projecting  ma- 
chines, is  shown  in  Fig.  81.  The  Icnob  on  the  front  may  be  moved 
to  the  right  or  to  the  left  to  change  the  amount  of  current  taken  by 
the  arc  lamp  from  the  power  mains.  For  alternating  current  only, 
the  rheostat  of  Fig.  81  may  be  replaced  by  the  Power's  Inductor 
Fig.  82,  but  not  for  direct  current. 


Fig.  82.     Power's  Inductor 


PATHE  PROFESSIONAL  MODEL  PROJECTOR 


The  Pathe  projecting  machine  introduced  into  America  is  the 
tvpe  known  as  their  "Professional  ]\Iodel."  The  Pathe  machine 
differs  in  one  essential  respect  from  all  other  projecting  machines 
which  have  reached  any  wide  sale  in  America,  in  that  it  is  made 
entirely  in  Europe,  being  made  in  the  Pathe  workshops  in  Paris. 
The  shops  there  employ  over  five  hundred  people  in  the  manufacture 
of  projecting  machines,  and  the  output  is  four  hundred  complete 


206 


1 


MOTION  HEAD  131 

machines  per  week,  the  result  of  gradual  growth  from  a  beginning 
which  dates  back  to  the  beginning  of  the  industry.  This  data  is 
here  given  to  inform  the  reader  that  the  Pathe  Professional  Model 
projector,  which  is  a  new  machine  to  the  American  public  and  to  the 
American  branch  of  the  motion-picture  industry,  is  not  an  experi- 
ment. 

Not  the  motion  head  alone,  but  every  part  of  the  entire  machine 
is  made  in  Paris.  It  is  urged  as  an  advantage  that  Europeans  are 
very  accurate  and  careful  in  building  machinery;  that  owing  to  the 
very  low  price  of  labor  more  time  can  be  given  to  the  work  of  each 
machine;  and  that  as  a  consequence  the  Pathe  Professional  INIodel 
projector  is  carefully  and  perfectly  constructed.  Against  this,  it  is 
urged  that  the  foreign  manufacture  is  an  objection  to  the  Pathe 
machine,  upon  the  assumption  that  in  the  case  of  a  breakdown  it 
would  be  hard  to  obtain  repairs.  Wa^^ng  aside  as  biased  the  usual 
manufacturer's  claim  that  the  machine  is  incapable  of  breakdown, 
full  weight  still  must  be  given  to  the  fact  that  Pathe  Freres  carry  a 
complete  stock  at  their  American  factory  at  Bound  Brook,  New 
Jersey,  and  at  their  offices  and  supply  stations  in  New  York,  Chicago, 
and  San  Francisco. 

All  this  is  not  for  the  purpose  of  boosting  the  Pathe  machine, 
but  for  the  purpose  of  making  the  reader  familiar  wdth  some  facts  of 
interest  in  connection  with  the  motion-picture  industry,  and  to  brush 
away  that  prejudice  which  the  patriotic  American  attaches  to  every- 
thing of  foreign  manufacture.  The  Pathe  machine  is  one  of  the 
foremost  in  use  in  America  today.  In  the  early  days,  there  was  no 
sale  for  a  machine  of  so  high  a  price,  but  with  the  steady  growth  of 
the  industry  Pathe  Freres  began  to  push  their  macliine  and  it  found 
a  wide  market. 

The  complete  Pathe  outfit  is  shown  in  Fig.  S3,  the  view  being 
taken  from  the  operator's  side  of  the  table. 

The  intermittent  movement  is  a  one-pin  Geneva  mechanism. 
The  star  wheel  and  pin  cam  are  placed  in  a  lubricating  box  to  reduce 
friction  and  wear  and  also  to  reduce  noise.  The  construction  of  the 
intermittent  mechanism  is  calculated  to  give  a  ratio  of  six  to  one, 
that  is,  one-sixth  motion  and  five-sixths  rest  for  the  total  picture 
interval.  This  is  with  a  view  to  giving  a  sharp  picture  free  from 
flicker,    ^^^len  the  light  is  not  crowded  to  its  limit,  the  Pathe  pro- 


207 


132 


THE  MOTION  PICTURE 


]'ector  is  capable  of  verv  delightful  projection,  and  the  operator  should 
set  about  getting  it.  With  the  stiff  table  legs  and  the  floor  "socles" 
as  Pathe  Freres  prefer  to  call  them,  the  machine  can  be  made  rigid. 
In  connection  wath  this,  the  manufacturers  recommend  an  arc  light 
using  only  twenty-five  amperes. 


Fig.  83.     Pathe  Professional  Outfit 


The  shutter  is  placed  in  front  of  the  lens.  It  is  a  three-wing 
multiple-blade  disk  shutter,  sixty  degrees  in  each  wing,  the  Ameri- 
can standard  shutter  for  all  modern  machines. 


f 


808 


MOTION  HEAD 


133 


The  film  feed  system  is  the  American  standard,  triple  sprocket 
system.  The  top  sprocket  runs  continuously,  feeding  the  film  from 
the  top  magazine;  the  middle  sprocket  is  intermittent,  for  stopping 
the  film  for  exposure  upon  the  picture  screen;  the  lower  sprocket 
runs  steadily  and  feeds  the  film  into  the  take-up  reel  in  the  lower 
magazine.  The  film  does  not  touch  the  mechanism  in  any  way  in 
the  center  or  picture  strip  of  the  film,  but  only  in  the  edges  where 


Fig.  84. 


Pathe  Mechanism  with  Magazines 
(rear  view)  Open 


the  perforations  are  placed,  reducing  as  much  as  possible  the  pull  or 
friction  upon  the  film  and  the  probability  of  scratching  or  damaging  it. 
The  framing  device  is  worked  by  a  small  lever  which  raises  or 
lowers  the  picture,  and  which  can  if  desired  be  locked  in  position  by 
a  thumb  screw. 


209 


134 


THE  MOTION  PICTURE 


The  automatic  fire  shutter  holds  the  film  window  of  the  motion 
head  normally  closed;  it  is  operated  to  lift  out  of  the  beam  of  light 
only  after  the  motion  head  has  begun  to  turn,  and  as  soon  as  the 
speed  is  reduced  for  the  purpose  of  stopping,  the  shutter  again  drops 
into  position  in  the  beam  of  light  and  protects  the  film  in  the  window. 

The  flame  shields  protect  the  film  from  exposure  to  the  light 
and  heat  of  the  lamp  and  lamp  house  from  the  time  it  leaves  the  upper 
magazine  until  it  is  wound  into  the  lower  magazine. 


Fig.  85.  ^Pathe  Arc  Lamps 

The  flame  shields  are  hinged  at  the  left,  as  are  also  the  safety 
.shutter  and  the  film  gate,  so  that  all  of  the  parts  in  front  of  the  film 
as  the  operator  views  it,  looking  at  the  back  of  the  motion  head,  may 
be  swung  out  of  the  way  for  inspection,  for  cleaning  up  the  path  of 
the  film,  and  for  threading  up  the  film  through  the  motion  head.    Fig. 


210 


MOTION  HEAD 


135 


84  shows  the  motion  head  thus  opened,  showing  also  the  magazines 
open  and  the  position  which  the  film  assumes  in  its  passage  through 
the  motion  head. 

The  fireproof  magazines  (upper  and  lower)  are  round,  with 
hinged  doors,  and  roller  film  outlet  and  inlet.  The  film  passes 
through  between  two  rollers  which  are  fitted  together  tightly  enough 
to  prevent  flame  from  getting  through  into  the  magazine,  yet  are  so 
constructed  as  not  to  scratch  or  injure  the  film  as  it  passes  between 
them. 

The  reels  in  the  magazines  arc  of  steel,  and  are  of  the  standard 
10-inch  size  for  1,000  feet  of  film. 

The  lamp  house  is  of  large  size.  It  has  doors  on  l)oth  sides  and 
a  slide  in  the  rear,  in  addition  to  which  the  top  lifts 
off,  enabling  the  operator  to  get  at  the  lamp  from  all 
sides,  and  from  the  top.  The  lamp  house  is  attached 
to  the  table  by  a  system  of  adjustable  sliding  rods 
which  permit  a  forward  and  backward  movement, 
as  well  as  a  side  movement  to  the  position  for  the 
stereo  lens  when  slides  are  to  be  projected. 

The  condenser  glasses  are  placed  in  a  cell 
which  is  so  designed  as  to  be  taken  out  of  its  sup- 
port easily  when  the  lamp  house  is  hot.  The  con- 
denser glasses  are  of  the  standard  American  size, 
4h  inches  in  diameter,  and  any  condensers  of  ^'^^^g 
this  size  used  in  any  other  projecting  machines 
may  be  used  in  the  Pathe  Professional — it  is  not  necessary  to  use 
an  imported  glass. 

The  slide  carrier  is  of  metal. 

The  arc  lamp  is  made  of  heavy  steel  and  bronze;  the  lamp 
itself,  removed  from  the  case,  is  illustrated  in  Fig.  85.  By  means  of  the 
top  fiber  knob,  the  operator  is  enabled  to  feed  the  carbons;  by  means 
of  the  next  knob,  the  small  one,  the  operator  is  enabled  to  shift  his 
light  from  left  to  right  or  from  right  to  left;  by  means  of  the  large 
knob  third  from  the  top,  the  operator  is  enabled  to  raise  or  lower 
the  light;  and  by  means  of  the  bottom  knob  he  is  enabled  to  move 
it  forward  or  backward  and  still  keep  it  under  perfect  control  all  of 
the  time.  The  carbon  holders  are  held  in  place  by  an  automatic 
device  which  does  away  with  the  necessity  of  tightening  them  with 


Pathe  Anti- 
Shake  Socle 


211 


136 


THE  MOTION  PICTURE 


a  screw.  This  automatic  device  also  prevents  the  carbons  from 
falling  because  of  the  expansion  of  the  metal  parts  holding  the  car- 
bon when  the  lamp  heats  up.  The  angle  or  slope  of  the  carbons  is  not 
adjustable. 

The  table  is  a  wood  top  with  adjustable  legs.     Each  leg  is  two 
telescopic  steel  tubes,  held  together  by  a  thumb  screw.     This  is 
showTi  clearly  in  Fig.  83,     By  the  adjustable  legs,  the  table  may 
be  leveled,  or  may  be  tilted  at  any  desired  angle  to  get  the  best  pic- 
ture upon   the  screen   possible  from 
any   enforced    location    of    the    pro- 
jector.     The   legs   may  be  attached 
rigidly    to    the    floor,  and    the    table 
shake  may  be  eliminated  by  the  use 
of  a  set  of  Pathe  "socles,"  illustrated 
in  Fig.  86. 

Rewinding  of  the  film  reel  is  not 
done  with  the  motion  head  but  with 
a  separate  simple  rewinder,  illus- 
trated in  Fig.  87. 

In  Fig.  88,  the  repair  parts  most 
likely  to  be  needed  are  illustrated 
and  numbered,  and  a  list  of  parts  by 
name  and  number  also  is  given. 
To  thread  up  the  Pathe  Profes- 
sional, first  open  up  both  gates  and  both  magazine  doors,  opening 
up  the  back  of  the  motion  head  as  is  shown  in  Fig.  84.  See  that 
the  framing  lever,  the  small  brass  handle  on  the  right  side  of  the 
machine,  is  about  in  the  center  of  its  motion,  that  is,  the  lever  should 
be  approximately  over  the  "h"  of  the  word  "Pathe"  on  the  quadrant 
in  which  the  framing  lever  turns. 

Place  the  film  reel  in  the  upper  magazine  so  that  the  film  un- 
winds from  the  top.  Xext,  pass  the  end  of  the  film  between  the 
two  magazine  rollers  in  the  film  outlet  which  is  found  on  the  lower 
part  of  the  magazine.  Close  the  upper  magazine  door.  Draw  out 
about  a  foot  of  film  and  mesh  it  over  the  upper  socket.  Now  place  the 
film  in  the  film  track,  first,  however,  making  a  loop  interiorly  in  the 
film  l)etween  the  upper  sprocket  and  the  film  track.  ]\Iesh  the  film 
over  the  intermittent  sprocket,  holding  the  loop  in  place  with  the 


Fig.  87.     Pathe  Film  Rewinder 


212 


MOTION  HEAD  137 

right  hand,  and  close  the  upper  gate.  Turn  the  shutter  with  the 
hand  until  the  film  moves  down,  then  mesh  the  film  over  the  lower 
sprocket,  allowing  for  a  loop  as  described  above.  The  lower  loop 
should  be  made  just  long  enough  to  avoid  touching  the  lower  chain 
gear  shaft.  A  turn  of  the  operating  handle  now  will  draw  film  enough 
through  the  machine  to  enable  the  operator  to  pass  it  between  the 
rollers  at  the  film  inlet  of  the  lower  magazine  and  from  there  to  the 
reel  hub,  where  it  is  fastened  in  the  usual  manner.  Turn  the  reel 
by  hand  to  tighten  up  any  slack  film  and  close  the  lower  magazine 
door  and  the  lower  film  gate  and  flame  shield.  Be  sure  that  the  groove 
in  the  lower  reel  fits  snugly  to  the  pin  in  the  lower  magazine  spindle. 
Both  the  top  and  lower  reels  are  designed  to  turn  counterclockwise 
and  on  no  account  should  the  spring  belt  of  the  magazine  be  crossed 
to  reverse  the  motion  of  the  lower  reel.  The  tightness  of  winding 
of  the  lower  reel  can  be  regulated  by  tightening  or  loosening  the 
two  milled  nuts  on  the  lower  magazine  spindle. 

The  manufacturers  offer  the  following  special  suggestions  for 
the  care  of  the  Pathe  Professional: 

The  fact  that  a  machine  is  strongly  built  is  no  reason  why  it  should  be 
abused.  All  machinery  requires  lubrication,  and  a  motion-picture  machine 
is  no  exception  to  the  rule. 

There  are  two  oil  cups  on  the  shutter  shaft.  Two  on  the  upper  sprocket 
shaft  and  two  on  the  lower.  Three  on  the  fly-wheel  shaft  and  two  on  the 
intermittent  sprocket  shaft.  One  on  the  upper  chain  gear  and  one  on  the 
toothed  gear  on  the  right-hand  side  of  the  machine.  There  is  also  another 
spur-gear  shaft  on  the  right-hand  side  with  two  oil  cups. 

The  star  wheel  runs  in  oil  and  the  lubrication  case  should  be  filled  daily. 
The  star  wheel  is  the  most  important  part  of  a  motion-picture  machine,  as 
upon  it  the  steadiness  of  the  picture  depends.  The  star  wheel  in  the  Pathe 
Professional  machine  is  accurately  adjusted  at  the  factory  and  should  not  be 
meddled  with. 

Only  the  best  quality  of  machine  oil  should  be  used  for  lubricating  the 
working  parts. 

The  film  tracks  and  sprockets  should  be  kept  clean  by  being  brushed 
occasionally  with  a  clean  tooth  brush.  The  film  tracks  may  be  rubbed  occasion- 
ally with  a  very  small  quantity  of  vaseline. 

The  window  frame  is  removable  for  cleaning  purposes.  It  should  not 
be  cleaned  with  a  knife  or  other  sharp  instrument,  l)ut  should  be  rubl^ed  with 
a  clean  stick  of  wood.  A  very  small  quantity  of  gasoline  sometimes  is  useful 
in  cleaning  the  film  sprockets  and  tracks. 


213 


138 


THE  MOTION  PICTURE 


SfO 


1     T 


5ie  5/3 


S19 


S/4 


s/s 


5/6 


5S0 


@ 
517 


SSI 


Fig.  88.     Pathe  Professional  Model  Parts 


214 


MOTION  HEAD 


139 


INDEX  OF  PARTS 


501 

Arc  lamp 

537 

Shaft  and  gear  for  framing 

502 

Asbestos-covered  wire  with  ter- 

538 

Shutter 

minal 

539 

Socket  screw 

503 

Oak  board 

540 

Spring  belt 

504 

Lamp  house,    sliding   base   and 

541 

Spring  for  tension  holder 

cone 

542 

Spring  for  top  of  door 

505 

Legs  and  flanges,  complete  set 

543 

Spring  for  window  frame 

506 

Mechanism  head  without  reels, 

544 

Upper  sprocket  with  shaft 

magazines  or  lenses 

545 

Lower  sprocket  with  shaft 

507 

Rheostat 

546 

Steel  sprocket  tension  holder 

508 

Slide  carrier 

547 

Steel  star  wheel 

509 

Double  pole  switch  and  cover 

548 

Upper  steel  roller 

510 

Automatic  shutter  shield 

549 

Stereopticon  attachment 

511 

Bolt 

550 

Steel  tension  roller  for  take-up 

512 

Chain 

551 

Steel  window  frame 

513 

Upper  chain  cogwheel  and  gear 

552 

Binding  post 

514 

Lower  chain  cogwheel 

553 

Carbon  holder 

515 

Steel  cog  gear,  28  teeth 

554 

Shaft  with  fiber  knob  and  gear 

516 

Steel  cog  gear,  35  teeth 

555 

Cone 

517 

Steel  cog  gear  for  take-up 

556 

Hood 

518 

Complete  door  with  shutter 

557 

Fiber  knob  for  door 

519 

Steel  film  track 

558 

Red  glass  for  door 

520 

Upper  flame  shield 

559 

Sliding  base 

521 

Lower  flame  shield 

560 

Sliding  rod,  15  inches 

522 

Fly  wheel 

561 

SHding  rod,  with  screw  end,  16 

523 

Framing  cog  gear 

inches 

524 

Bronze  gear,  112  teeth 

562 

Condenser   lens,    bi-convex,    4^ 

525 

Gear  guard 

inch  diameter 

526 

Gear  for  shutter  shaft 

563 

Condenser    lens,    plano-convex, 

527 

Handle 

4^  inch  diameter 

528 

Handle  for  framing  device 

564 

Condenser   lens,    meniscus,     4h 

529 

Intermittent  steel  sprocket 

inch  diameter 

530 

Upper  magazine 

565 

Condenser  mount   without   lens 

531 

Lower  magazine 

566 

Motion  picture  jacket 

532 

Milled  screw 

567 

Motion  picture  lens,  any  focal 

533 

Steel  pin  wheel 

length 

534 

Rack 

568 

Stereopticon  lens  without  mount 

535 

Steel  reel,  10-inch 

any  focal  length 

536 

Roller  for  magazines 

569 

Stereopticon  mount  without  lens 

215 


140 


THE  MOTION  PICTURE 


THE  STANDARD  PROJECTOR 

The  unique  feature  of  the  "Standard,"  or  ".\inerican,"  pro- 
jector is  in  the  fihn  protection.  Other  machines  provide  fireproof 
magazines  and  numerous  devices  for  protecting  the  fihn  from  the 
heat  of  the  lamp,  while  passing  from  the  upper  to  the  lower 
magazine,  and  still  other  shields  for  preventing  the  film  from 
coming  in  contact  with  the  lamp  house  when  running  out  of  the 
projecting  head  under  the  feed  of  the  upper  sprocket. 


Fig.  89.     No.  2  "Standard"  .\utomatic  Moving-Picture  Machine  with  Motor 


The  "Standard"  attacks  this  problem  in  a  different  way.  A 
complete  enclosed  housing  for  the  film  is  created,  including  the  upper 
reel,  the  motion  head,  and  the  lower  reel.  The  entire  length  of  the 
film  strip  is  protected  and  is  completely  enclosed,  with  the  exception 
of  the  single  image  in  the  film  window.  The  motion  head  is  box-like 
in  construction.  The  upper  feed  magazine  is  placed  over  the  motion 
head  and  close  upon  it,  leaving  no  space  between  in  which  the  film 


216 


MOTION  HEAD  141 

can  be  exposed  in  passing  from  the  feed  magazine  box  to  the  motion- 
head  box.  The  lower  take-up  magazine  is  placed  just  below  the 
projection  lens  artd  against  the  front  of  the  motion-head  box,  leav- 
ing again  no  space  between  where  the  film  is  exposed  in  passing  from 
the  motion  head  to  the  take-up  magazine. 

Because  of  the  close  fitting  of  the  magazines  to  the  box  body 
of  the  projection  head,  no  film-friction  film  outlets  are  used  upon 
the  magazines,  either  upper  or  lower,  a  flame  trap  being  built  into  the 
box-like  motion-head  frame. 

The  close  construction  of  the  three  parts,  upper  magazine, 
motion  head,  and  lower  magazine,  and  the  full  protection  of  the  strip 
of  film,  is  shown  clearly  in  Fig.  89,  giving  a  general  view  of  the  "Stand- 
ard" projection  equipment.  Xot  only  are  the  motion  head  and 
magazines  shown,  but  also  the  "Standard"  table,  built  wholly  of 
metal  rods  and  tubes,  the  lamp  house,  and  the  motor.  The  show- 
ing of  the  motor  in  the  picture  recalls  the  fact  that  at  one  time  the 
"Standard"  was  the  only  projection  machine  which  was  permitted 
to  run  by  motor  in  New  York,  all  others  being  compelled  to  turn  by 
hand.  The  feature  of  distinction  upon  which  this  discrimination 
was  based  was  that  the  film  could  not  be  fed  by  the  motor  and  up- 
per sprocket  to  make  contact  with  the  lamp  house  or  to  fall  into  the 
beam  of  light  outside  of  the  motion  head,  because  of  the  enclosed 
box  construction  of  the  entire  film-handling  mechanism  and  maga- 
zines. 

The  "Standard"  does  not  use  the  opaque  shutter,  but  uses  a 
semi-opaque  or  translucent  shutter  which  gives  a  soft  haze  to  the 
picture  screen  during  the  short  interval  of  shift  of  the  film.  By 
changing  the  interval  of  darkness  into  an  interval  of  haze,  the  flicker 
is  reduced;  and  the  claim  is  made  also  that  an  equal  screen  illumina- 
tion is  produced  with  a  smaller  current  consumption  in  the  lamp. 
This,  however,  lies  with  the  operator;  the  rule  of  less  light  and  smoother 
'picture  or  more  light  and  more  flicker  is  a  fundamental  principle  in  the 
optics  of  the  motion-picture  system  when  projection  by  persistence 
of  vision  is  practiced,  and  it  applies  to  the  "Standard"  machine 
along  with  the  others.  There  is  room  for  the  exercise  of  the  oper- 
ator's skill  with  all  of  them  in  the  matter  of  flicker. 

The  operator  must  discriminate  between  "flicker,"  which  is  the 
variation  of  the  intensity  of  the  light  by  which  the  screen  seems  to 


217 


142 


THE  MOTION  PICTURE 


wink  at  the  spectator,  and  "jiggle,"  which  is  the  dancing  about  of 
the  fixed  objects  of  the  projected  picture,  due  eitlier  to  faulty  in- 
termittent mechanism  or  film  gate  adjustment,  or  to  an  unsteady 
table  which  yields  to  the  force  applied  to  the  crank  handle. 

The  single  image  of  the  film  which  is  in  the  film  window  is 


Fig.  90.     "Standard"  Motion  Head 

guarded  from  the  heat  of  the  lamp  by  a  hinged  shutter  which  falls 
over  the  window  when  the  driving  mechanism  of  the  machine  is  not 
in  motion.  When  the  motion  head  is  l^eing  driven  at  projecting 
speed,  a  speed  governor  acts  to  engage  and  life  the  safety  shutter 
from  the  film  window^  and  to  hold  it  up  as  long  as  the  speed  of  the 
motion  head  continues,  dropping  it  before  the  window  as  soon  as  the 
motion  stops. 


218 


MOTION  HEAD  143 

The  intermittent  movement  of  the  fihii  is  obtained  by  the  usual 
arrangement  of  Geneva  mechanism.  The  Geneva  pin  wheel  is  so 
built  that  when  the  pin  becomes  worn  a  new  one  may  be  installed 
to  replace  the  worn  one. 

The  lamp  house  is  adjustable  toward  or  from  the  motion  head 
by  sliding  its  cross  track  directly  upon  the  two  metal  tubular  rails 
which  form  the  top  bars  of  the  operating  table  or  frame.  The  cross 
track  is  a  pair  of  parallel  bars  to  permit  the  lamp  house  to  be  slid  over 
for  the  stereo  lens  of  the  motion  head  as  reciuired. 

The  construction  of  the  motion  head  and  the  course  of  the  film 
through  it  is  shown  in  greater  detail  in  Fig,  90,  where  the  side  of  the 
motion-head  box  and  the  film  gate  door  and  back  plate  or  "back 
door"  of  the  motion  head  are  removed  to  reveal  the  mechanism. 

The  principal  parts  of  the  "Standard"  machine  which  are  likely 
to  be  required  for  repairs  are  shown  in  Fig.  91  with  their  identifi- 
cation numbers;  in  addition,  a  list  of  the  parts  by  name  is  given  with 
their  numbers. 

The  lamp  of  the  "Standard"  machine  removed  from  the  lanip 
house  in  order  to  reveal  all  of  its  parts,  is  shown  in  Fig.  92,  The 
knob  D  feeds  the  carbons.  The  knob  B  for  tilting  the  lamp  and  the 
knob  C  for  raising  and  lowering  it  are  together,  the  knob  C  l)eing 
upon  a  rod  and  the  knob  B  being  upon  a  tube  which  is  sleeved  over 
the  rod.  This  distinction  of  a  double  knob  as  compared  with  a 
single  knob  will  help  the  operator  to  avoid  the  eiTor  of  turning  the 
wrong  knob  and  throwing  his  screen  lighting  out  of  adjustment 
when,  with  his  eyes  on  the  screen  and  his  right  hand  turning  the 
crank,  he  reaches  with  his  left  hand  to  feed  the  carbons.  If,  under 
such  circumstances  his  hand  touches  the  doul)le  knob,  he  will  not 
turn  it  by  mistake.  The  knob  E  moves  the  lamp  toward  or  from 
the  condensers. 

The  adjustment  of  the  angle  of  the  carbons  with  respect  to  each 
other  is  attained  only  through  the  door  of  the  lamp  house,  by  turn- 
ing the  knob  G  for  the  lower  carbon,  or  H  for  the  upper  carbon. 
By  these  knobs,  the  carbon  holders  may  be  set  for  direct-current  or 
alternating-current  positions,  the  difference  in  alignment  between 
the  centers  of  the  upper  and  the  lower  carbons  of  the  direct-current 
setting  also  being  controlled  by  the  knobs  G  and  H.  Knobs  A  and 
F  are  lock  knobs  for  the  carbon  pencils  in  the  holders. 


219 


144 


THE  MOTION  PICTURE 


INDEX  OF  PARTS 

1  Star     wheel     and    spindle     (one         7     Collar  1 

piece)  8     Gear  i   On    fly    wheel 

2  Bushing  on  intermittent  spindle  9     Bronze  bearing   |      spindle 

(short)  10     Collar 


Fig.  91.     Repair  Parts  for  "Standard"  Projector 


3  Intermittent  sprocket 

4  Bushing  on  intermittent  spindle 

5  Fly  wheel  spindle 
0  Fly  wheel 


1 1  Pin  wheel 

12  Engaging  pin  for  pin  wheel 

Hi     Screw  to  hold   pin  in  pin  wheel 
(hardened) 


i 


220 


MOTION  HEAD 


145 


14 

15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
31 
32 
33 

34 
35 
36 
37 
38 
39 
40 
41 
42 

43 
44 
45 
46 

47 
48 
49 


Bronze    bearing    for    fly     wheel 

spindle 
Gear  connecting  with  shutter  gear 
Revolving  shutter  and  spindle 
Revolving  shutter  gear 
Driving  shaft  spindle 
Chain  sprocket 


Collar 
Spiral  gear 
Clutch  collar 


On   driving 
shaft 


J 


Handle  for  driving  (complete) 
Transmission  spindle 
Gear  42  teeth 


12 
15 


On   transmis- 
sion spindle 


Stereopticon  bracket 
Stereopticon  bar,  short 
Stereoption  bar,  long 
Stereopticon  ring  casting 
Mechanism  fastening  casting 
Screw  for  mechanism  fastening 

casting 
Motor  fastening  casting 
Governor  spindle 
Sliding  gear  on  governor 
Governor  head 
Governor  wings  (each) 
Governor  arms  (each) 
Governor  pin 
Governor  collar 
Gear    on    governor    spindle     (8 

teeth) 
Fire  shutter  (complete) 
Door  for  machine  (complete) 
Aperture  tension  cradle 
Filni  tension  guide  (intermittent 

sprocket) 
Door  lock  (complete) 
Film  slide  and  cradle  (complete) 
Springs     for     aperture     tension 

cradle  (each) 


50 
51 

52 
53 
54 
55 
56 
57 
58 
59 
60 
61 
62 
63 
64 
65 
66 
07 
68 
69 
70 

71 


73 

74 
75 

76 
77 
78 
79 
80 
81 
82 
83 
84 


Aperture  plate 

Guiding  spool  for  film  track  (com- 
plete) 
Film  shutc 

Upper  film  sprocket  spindle 
Upper  film  sprocket 
Gear    I  On  upper    film  sprocket 
Collar  J     spindle 

Upper  idler  roller  lever  (complete) 
Lower  film  sprocket  spindle 
Lower  film  sprocket 
Gear     1  On  lower    film    sprocket 
Collar  j     spindle 
Framing  device  spindle 
Framing  device  eccentric 
Framing  device  handle 
Framing  device  sliding  ])ox 
Screw  adjustment  for  sliding  box 
Carbon  holder  for  A.  C.  (each) 
Carbon  holder  for  D.  C.  (each) 
Reel  spindle  (upper  magazine) 
Collar    on    reel    spindle     (upper 

magazine) 
Reel  spindle  with  collar  and  lock 

nut  (lower) 
Take-up  bracket  with  tightening 

nut 
Friction     plate     on     lower     reel 

spindle 
Friction  washer 

Large  chain  sprocket  on   take-up 
Spring  on  takq-up 
Chain  on  take-up 
Spindle  for  eccentric  on  take-up 
Eccentric  bushing  on  take-up 
Set  screw  for  eccentric  on  take-up 
Small  chain  sprocket  on  take-up 
Chain  (take-up  to  mechanism) 
Carbon   holder   tightening   screw 
Switch  and  switch  box  with  nickel 
base 


221 


146  THE^MOTION  PICTURE 

To  thread  the  fihn  through  the  motion  head,  slide  the  full  feed 
reel  over  the  spindle  in  the  upper  magazine.  Open  the  back  door  of 
the  motion-head  box.  Pass  the  end  of  the  film  between  the  two 
flame-trap  rollers  on  the  top  plate  of  the  motion-head  box  near  the 
upper  sprocket;  then  under  the  upper  sprocket;  let  the  pair  of  clamp 


WIRE  CONNECTION 


Fig.  92.     Electric-Arc  Lamp  for  "Standard"  Projector 

rollers  rest  upon  the  film,  holding  it  against  the  upper  sprocket. 
Turn  the  framing  lever  "up"  as  far  as  it  will  go,  to  make  the  upper 
feed  loop  as  large  as  possible;  then  turn  the  fly  wheel  by  hand  until 
the  intermittent  sprocket  just  starts,  then  make  an  upper  feed  loop 
so  that  it  will  come  ^  inch  under  the  top  plate  of  the  motion-head 
box;  pa.ss  the  film  down  the  guides  and  over  the  teeth  of  the  inter- 
mittent; make  a  small  loop  to  lower  sprocket  and  close  the  door. 
The  film  passes  through  the  lower  chute  to  take-up  magazine  and  is 
attached  to  the  hub  there  in  the  usual  manner.  Take  up  the  slack 
by  turning  the  take-up  reel  by  hand,  and  give  a  half  turn  of  the  driv- 
ing crank  to  see   that  the  film  is  being  taken  up  properly  before 


'  222 


MOTION  HEAD  147 

closing  the  door  of  the  lower  magazine.  The  precaution  in  forming 
the  upper  loop  is  necessary  for  the  reasons  that  (1)  if  the  upper  loop 
is  formed  with  the  frame  lever  "down"  by  which  the  size  of  the  upper 
loop  may  be  increased  when  the  frame  lever  is  throw^n  "up,"  then 
the  upper  loop  when  thus  increased  may  let  the  film  rub  against  the 
inside  of  the  top  of  the  motion-head  box;  and  (2)  if  the  upper  loop  is 
formed  as  large  as  possible  when  the  intermittent  has  just  finished 
its  pull,  the  upper  steady  feed  will  feed  a  full  picture,  or  f  inch  of  film, 
into  the  upper  loop  before  the  intermittent  pulls  again,  thereby  in- 
creasing the  size  of  the  upper  feed  loop  and  perhaps  permitting  the 
film  to  rub  against  the  inside  surface  of  the  motion-head  box. 

The  take-up  device  is  adjusted  by  a  lock  nut  attached  to  the 
spindle  of  the  lower  magazine  box.  To  adjust  the  tension,  loosen 
the  small  screw  in  the  lock  nut.  A  turn  then  to  the  right  will  irive 
more  tension,  and  a  turn  to  the  left  will  give  less  tension.  Wlien 
the  tension  is  readjusted  to  suit,  tighten  the  small  set  screw  in  the 
lock  nut  again  to  hold  the  adjustment. 

^Mien  the  star  wheel  becomes  worn  or  loosened,  it  can  be  ad- 
justed to  the  pin  wheel  by  loosening  the  four  screw^s  which  hold  the 
bronze  bearings  in  place.  To  tighten  the  star  wheel  to  the  pin  wheel, 
give  both  bronze  bearings  a  slight  but  equal  turn  upward  and  again 
fasten  the  four  set  screws  which  hold  the  bearings  fixed  as  adjusted. 

The  mechanism  should  be  oiled  thoroughly  before  beginning 
each  afternoon  or  evening  run.  Do  not  forget  to  oil  the  leather 
washer  between  the  flange  and  the  large  chain  sprocket.  Oil  the 
spindle  from  an  oil  hole  inside  the  box. 

THE  REWINDING  "STANDARD"  PROJECTOR 

This  projector  is  shown  in  Fig.  93.  The  take-up  reel  is  in  the 
square  box  below  and  in  front  of  the  motion-head  box,  while  the 
feed  reel,  instead  of  being  mounted  edgewise  above  the  motion- 
head  box,  is  mounted  flat. 

The  operation  of  this  machine,  which  is  classed  as  an  "auto- 
matic rewinding  projector,"  is  not  that  it  automatically  rewinds  the 
film,  nor  that  it  rewinds  it  at  all,  but  that  it  uses  the  film  for  a  second 
and  third  projection,  and  as  many  projections  as  required,  without 
rewinding  it  at  all.  The  top  magazine,  or  feed  magazine  feeds 
from  the  middle  of  the  reel. 


223 


148 


THE  MOTION  PICTURE 


Film  reels  received  from  the  film  exchanges  usually  are  wound 
with  the  title  end  outside.  When  so  received,  the  reel  must  be 
rewound  before  it  is  placed  in  the  feed  magazine  of  this  "Automatic 
Rewinder"  machine;  and  indeed,  when  the  film  is  received  with  its 
leader  inside  the  roll,  as  this  machine  requires  it,  the  film  must  be 
rewound  twice,  to  get  it  into  a  roll  with  a  large  opening  in  the  mid- 
dle. Having  reeled  the  film  up  with  a  large  center  opening,  and 
with  the  leader  and  title  inside  of  the  roll,  the  roll  is  dropped  into  the 
horizontal  round  feed  magazine,  the  leader  end  is  taken  in  the  middle 


Fig.  93.     The  Rewinding  "Standard"  Projector 

of  the  roll  and  is  passed  down  through  the  floor  of  the  feed  maga- 
zine into  the  film  inlet  of  the  motion-head  box,  passing  over  the 
guides  provided;  the  motion-head  mechanism  then  is  threaded  with 
care  for  the  upper  and  lower  loop  size,  as  described  for  the  "Stand- 
ard" machine.  Fig.  90,  and  the  leader  end  is  taken  into  the  take-up 
magazine  and  attached  to  the  take-up  reel,  which  has  a  large  arbor, 
so  that  the  film  is  rewound  with  a  large  opening  in  the  middle. 

Projection  is  made  by  crank  or  motor,  the  strip  of  film  feeding 
from  the  center  of  the  feed  magazine  and  winding  up,  head  in,  upon 
the  take-up  device. 


224 


MOTION  HEAD  149 

AMien  the  strip  of  film  has  been  completed,  the  operator  lets  the 
tailpiece  run  through  until  it  is  completely  wound  upon  the  take- 
up  reel.  He  then  opens  both  the  take-up  magazine  and  the  empty 
feed  magazine,  takes  the  film  off  of  the  take-up  device  without  the 
reel,  and  places  the  film  without  the  reel  in  the  feed  magazine,  starts 
the  inside  end  of  the  film  down  through  the  floor  of  the  feed  maga- 
zine and  over  the  guides,  threads  up  the  motion-head  mechanism, 
attaches  the  leader  to  the  take-up  mechanism,  closes  up  the  doors, 
and  is  ready  for  projection  again,  repeating  as  often  as  his  program 
requires.  \Yhen  a  program  of  two  or  three  reels  is  being  run,  one  reel 
after  another,  the  old  reel  is  lifted  from  the  take-up  device  and  placed 
flat  in  a  metal  storage  box,  placed  upon  the  shelf  flat  to  keep  the  open 
roll  or  hank  of  film  from  collapsing,  and  the  new  hank  is  dropped 
into  the  feed  magazine.  Xo  rewinding  ever  is  required  except  to  get 
the  film  into  proper  form  for  the  feed  magazine  when  it  is  received 
from  the  film  exchange  or  factory,  and  to  wind  it  up  again  upon  a 
small  arbor  to  pack  it  in  the  small  shipping  box  in  which  it  was  re- 
ceived from  the  exchange. 

This  machine  is  no  longer  offered  for  sale  by  the  manufacturers, 
and  theaters  equipped  with  them  may  have  the  special  magazines 
replaced  with  the  later  type,  requiring  rewinding,  if  the  automatic 
rewinding  feature  is  not  entirely  satisfactory. 

THE  SELIQ  POLYSCOPE 

The  old  style  Polyscope,  made  by  the  Selig  Company,  has  been 
withdrawn!  from  the  market.  It  used  the  pin-shift  mechanism  con- 
trolled by  two  cams  on  the  main  driving  shaft. 

The  Polyscope  projector  now  sold  by  the  Selig  Company  is  il- 
lustrated complete  in  Fig.  94,  and  its  motion  head  is  shoA\Ti  in  closer 
detail  in  Fig.  95,  the  door  of  the  film  gate  being  opened. 

The  film  feeding  mechanism  is  the  American  standard,  three- 
sprocket,  with  Geneva  intermittent  drive. 

In  threading  up  the  film,  the  feed  reel  is  placed  in  the  magazine 
on  the  top  of  the  motion  head,  the  end  of  the  film  is  taken  through  the 
film  outlet  rollers,  and  the  door  of  the  feed  magazine  is  closed. 

By  finger  pressure  upon  a  projecting  lug,  the  presser  roller  is 
lifted  from  the  upper  constant  feed  sprocket  until  the  film  is  placed 
upon  the  sprocket  and  meshed  with  the  teeth. 


225 


150 


THE  MOTION  PICTURE 


The  frame  lever  is  now  framed  "down"  to  take  out  any  slack 
which  might  be  above  the  film  gate,  the  film  is  placed  in  the  track 
of  the  film  gate  with  a  slight  slack  above — at  least  one  picture  length 
— then  meshed   with   the  intermittent  sprocket,   and   the  film-gate 


Fig.  94.     Selig  Polyscope  Projector 

door  is  closed.  This  causes  the  guide  roller  at  the  top  of  the  door 
to  engage  the  edges  of  the  film,  and  presses  the  pre-sser  roller  against 
the  intermittent  sprocket,  both  of  these  rollers  being  carried  by  the 
door.  This  step  in  threading  might  seem  at  first  to  require  three 
hands  on  the  operator,  but  the  trick  is  to  hold  the  end  of  the  film 
below  the  intermittent  with  the  left  hand,  to  press  the  film  above  the 
motion-head  frame  with  the  long  finjjer  of  the  riijht  hand  and  stretch 
it  tight  over  the  film  window  and  along  the  film  track  of  the  gate,  then 


226 


MOTION  HEAD 


151 


Fig.  95.     Sclig  Polyscope  Motion  Head 


227 


152 


THE  MOTION  PICTURE 


to  swing  the  door  shut  with  the  thunib  of  the  right  hand,  which 
will  be  almost  engaging  the  top  guide  roller  of  the  gate. 

Now  frame  "up"  and  give  a  little  slack  in  the  lower  feed  loop, 
then  pass  the  film  down  into  the  magazine  box,  or  to  the  take-up 
reel  if  one  is  userl. 

The  Selig  lamp  house  has  the  feature  of  sliding  the  lamp  en- 


Fig.  96.     The  Selig  Lamp 

tirely  out  of  the  house  to  make  inside  adjustments,  and  to  set  the 
carbons.  Fig.  94  shows  the  lamp  withdrawn  from  the  lamp  house. 
Before  projection  is  begun,  the  lamj)  is  pushed  in  until  the  vertical 
panel  at  the  back  of  the  lamp  closes  with  the  body  of  the  lamp  house 
and  forms  a  closed  house.  The  controlling  knobs  have  universal 
joints,  permitting  them  to  pass  through  very  small  holes  in  the  back 
panel  of  the  lamp  house,  and  yet  reach  and  operate  their  different 
parts  of  the  lamp  in  any  position  of  adjustment. 

Four  knobs  are  provided  outside  the  lamp  house,  for  lateral, 


228 


MOTION  HEAD  153 

transverse,  vertical,  and  feed  movements  of  the  lamp.     The  angle  of 
the  carbons,  either  jointly  for  direct  current  or  separately  for  alter- 
nating current,  is  adjusted  by  drawing  the  lamp  from  the  house  and 
working  upon  adjustments  normally  inside  of  the  lamp  house. 
The  Selig  lamp  is  illustrated  in  detail  in  Fig.  96. 

THE  EDENQRAPH  PROJECTOR 

In  the  general  design  of  this  machine,  the  manufacturer  has 
planned  for  the  most  direct  film  path  possible,  and  for  the  separa- 
tion of  the  film  path  from  all  entangling  mechanisms  as  far  as  it  is 
possible  to  do  so.  The  path  of  the  film  is  "in  the  open  air"  as  com- 
pletely as  it  is  possible  to  make  it,  from  the  outlet  of  the  feed  maga- 
zine to  the  inlet  of  the  take-up  magazine.  Fig.  97  shows  the  Eden- 
graph  in  general  view. 

In  Fig.  98  a  close  view  of  the  motion  head  and  magazines  of  the 
Edengraph  are  given,  from  which  also  the  threading  of  the  machine 
may  be  seen  clearly. 

After  placing  the  feed  reel  in  the  upper  magazine,  the  leading  end 
of  the  film  may  be  inserted  into  the  outlet  valve  by  slipping  it  through 
the  slot  in  the  side  of  the  valve;  it  will  then  be  properly  placed  be- 
tween the  two  pairs  of  rollers,  for  there  are  four  rollers  in  each  of  the 
film  valves.  The  film  is  now  carried  around  the  upper  sprocket, 
which  is  as  close  as  can  be  to  the  upper  film  outlet,  and  is  pressed 
to  the  upper  sprocket  by  the  single  presser  roller.  The  film  is  then 
taken  over  the  flanged  guide  roller  at  the  top  of  the  film  gate,  the 
film  gate  is  opened,  and  the  film  is  carried  down  the  film  track  to 
the  intermittent,  leaving  a  sufficient  slack  at  the  top  of  the  gate  for 
the  top  feed  loop;  the  gate  then  is  closed.  The  film  is  now  brought 
around  the  lower  sprocket  and  taken  into  the  take-up  magazine 
through  another  four-roller  film  valve  and  attached  to  the  take-up 
reel  in  the  usual  manner.  A  turn  of  the  crank  will  show  that  the 
take-up  and  feed  elements  are  working  properly,  when  all  doors 
may  be  closed  and  the  machine  is  ready  for  projection. 

The  film  is  rewound  by  a  separate  rewinder. 

The  gears  of  the  motion  head  are  all  contained  within  the  box- 
like frame,  but  are  accessible  by  taking  off  the  side  of  the  box  next 
to  the  stereo  lens,  first  swinging  the  stereo  lens  out  of  the  way,  as 
shown  in  Fig.  99. 


229 


154 


THE  MOTION  PICTURE 


Fig.  97.     The  Edengraph  Projector 


230 


I. 


MOTION  HEAD 


155 


Fig.  98.     Detail  View  of  the  Edengrapb  Motion  Head 


231 


156 


THE  MOTION  PICTURE 


Fig.  99.     Edcngraph  Gear  Case  of  Motion  Head 


232 


MOTION  HEAD 


157 


Fig.   100.     The  Edengraph  Motion-Picture  ^Mechanism 
with  the  Film  Gate  Swung  Open  on 
Its  Hinge 


Fig.   101.     The  Edengraph  Geneva  Box 


233 


158 


THE  MOTION  PICTURE 


Fig.   102.     The  Edengraph  Lamp  Adjusted  for  Alternating  Current 


Fig.   103.     The  Edengraph  Lamp  Adju.sted  for  Direct  Current 


234 


o  -51: 
<!  &^= 
m  .'-^ 
w  ^  =, 
ai  M  ; 
o<  => 
OS  . 

a  ■?  ? 

.      c  a 

Spa 

o  -     » 

o  =  ^ 

w  1^2 


MOTION  HEAD  I59 

The  film  gate  door  of  the  Edengraph  is  pivoted  at  the  bottom, 
instead  of  at  the  side  as  is  customary;  the  argmnent  is  that  the  pres- 
sure upon  both  edges  of  the  film  will  be  e(jual  witli  this  method  of 
construction.  The  two  fire  shields  are  attached  to  the  film  gate  door 
for  the  protection  of  the  upper  and  lower  feed  loops.  This  detail  is 
shown  in  Fig.  100. 

The  intermittent  drive  is  the  Geneva  type  of  mechanism,  en- 
closed in  an  oil  box,  the  intermittent  shaft  projecting  through  the 
wall  to  pass  outside  of  the  motion-head  frame  to  the  film  gate,  Fig. 
101. 

The  Edengraph  lamp  has  three  control  knobs,  the  diagonal 
knob  being  carbon  feed,  the  upper  level  rod  being  the  adjustment 
for  height,  and  the  bottom  knob  being  the  adjustment  for  distance 
from  the  condensers.  The  adjustment  for  angle  and  the  adjust- 
ment to  the  right  or  left  is  made  inside  the  lamp  house.  Two  views 
of  the  Edengraph  lamp  are  given  in  Figs.  102  and  103,  the  lamp  in 
Fig.  102  ])eing  shown  atljusted  for  alternating-current  arc  and  the 
one  in  Fig.  103  for  direct-current  arc. 

THE  LUBIN  PROJECTOR 

Lubin's  "Marvel"  is  shown  in  general  view  in  Fig.  104.  A  near 
view  of  the  motion  head,  with  the  film  gate  door  open,  is  shown  in 
Fig.  105.  In  this  device,  the  flame  shield  is  pivoted  to  the  operating 
table  below,  and  attached  to  the  gate  door  above. 

The  safety  shutter  is  operated  by  a  friction  clutch,  which  must 
be  kept  clean  and  free  from  oil. 

To  set  up  the  machine,  the  motion  head  is  fastened  to  the  table 
by  means  of  the  thumb  screw  which  also  holds  the  front  leg  of  the 
table.  The  belt  from  the  motion  head  to  the  lower  magazine  take-up 
shaft  is  crossed  to  turn  the  shaft  in  the  proper  direction. 

The  automatic  fire  shield  must  stand  so  that  if  the  lamp  house 
is  in  line  with  the  mechanism  the  fire  shield  stands  straight  between 
the  two.  Hook  the  fire  shield  to  the  lamp  house  by  means  of  the 
adjustable  rod.  AMien  in  proper  position,  the  fire  shield  must  al- 
most touch  the  table. 

Slide  the  electric  lamp  and  the  stand  provided  for  it  into  the 
lamp  house  and  fasten  by  means  of  the  shortest  handle,  which  also 
serves  to  raise  or  lower  the  lamp. 


235 


160 


THE  MOTION  PICTURE 


The  condensers  are  placed  in  the  holder  with  the  round  sides 
facing  each  other. 


Fig.   10-1.     General  View  of  the  Lubin  Projector 

To  thread  the  film,  push  the  lamp  house  to  the  left.  This  opens 
the  fire  shield  and  leaves  the  motion-head  mechanism  free.  Place 
the  full  feed  reel  in  the  upper  magazine.     The  film  must  unwind 


236 


I 


MOTION  HEAD 


161 


toward  the  left,  and  the  emulsion  or  dull  side  of  the  film  must  be  to- 
ward the  lamp  house,  the  figures,  of  course,  being  upside  down,  or 
heads  down,  and  the  leader  or  title  being  on  the  outside  end  of  the 


Fig.   105.     Detailed  View  of  the  Lubin  Motion  Head 

reel.  Pull  the  film  through  the  rollers  of  the  flame-trap  or  film  out- 
let attached  to  the  lower  part  of  the  magazine.  Close  the  door  of 
the  magazine  and  fasten  with  the  catch.     Bring  the  film  to  the  top 


237 


162  THE  MOTION  PICTURE 

sprocket,  press  downi  the  rollers  underneath,  lay  the  film  around  the 
right  side  of  the  sprocket  and  close  the  rollers  to  press  the  film  against 
the  sprocket,  seeing  that  the  teeth  of  the  sprocket  mesh  properly 
with  the  holes  in  the  film. 

Open  the  film-gate  door.  Now  press  down  the  framing  lever 
fully.  This  lowers  the  framing  carriage.  Bring  the  film  between 
the  door  and  the  tension  plate  of  the  gate,  carrying  it  accurately 
down  through  the  film  guide  of  the  film  gate,  and  close  the  door. 
This  door  may  be  closed  before  adjusting  the  film  to  the  intermittent 
sprocket. 

Pull  up  the  film,  so  as  to  leave  a  loop  big  enough  to  place  over 
your  thumb  between  the  top  sprocket  and  the  door  rollers.  Turn 
the  fly  wheel  by  hand  until  the  middle  sprocket — intermittent  feed 
sprocket — starts,  but  before  it  moves  any  distance  stop  and  open 
the  presser  rollers  and  place  the  film  upon  the  middle  sprocket 
meshing  it  carefully  with  the  teeth  of  the  sprocket,  and  letting  the 
presser  rollers  down  upon  it  to  hold  it  in  place,  the  rollers  pressing 
the  film  to  the  hubs  of  the  sprocket  teeth. 

Now  raise  the  carriage  fully  by  means  of  the  framing  lever. 
Open  the  presser  rollers  of  the  bottom  sprocket  and  place  the  film 
around  the  sprocket,  but  leave  just  loop  enough  to  touch  the  back 
guard,  putting  the  teeth  of  the  sprocket  properly  through  the  film. 
Close  the  rollers,  so  that  the  film  now  lies  between  the  bottom  sprocket 
and  the  rollers,  the  rollers  being  on  top. 

Push  the  film  through  the  two  rollers  in  the  bottom  magazine, 
turning  the  handle  of  the  motion  head  to  give  a  sufficient  slack  to 
reach  the  arbor  of  the  take-up  device.  Attach  to  the  arbor  in  the 
usual  way,  take  up  the  slack  by  turning  the  take-up  reel  by  hand, 
then  turn  the  crank  a  part  of  a  turn  to  see  that  the  take-up  is  work- 
ing properly,  and  close  the  lower  magazine  door. 

After  everything  is  in  place,  turn  on  the  light,  but  be  sure  that 
the  fire  shield  is  closed.  ^Vhen  starting  projection,  press  the  main 
crank  and  handle  somewhat  toward  the  left.  This  will  bring  the 
friction  clutch  into  action.  Also  notice  before  every  projection  of 
a  reel  that  the  automatic  fire  shutter  is  working  properly.  Should 
the  fire  shutter  refuse  to  work,  there  is  either  oil  or  dirt  in  the  fric- 
tion clutch  to  which  the  chain  is  attached  on  the  main  shaft  gf  the 
handle.     Never  oil  the  friction  clutch.     In  case  of  dust  or  oil  com- 


238 


MOTION  HEAD  163 

ing  into  this  clutch,  wipe  it  out  clean  and  dry.     Now  open  the  door 
of  the  fire  shield,  turn  the  handle  and  proper  projection  may  he  made. 

GENERAL  NOTE 

Before  taking  the  instructions  for  any  particular  machine  as  final, 
remember  that  there  are  many  general  rules  which  apply  to  all  machines, 
and  these  have  been  discussed  under  the  subject  of  the  motion  head  and 
motion-picture  projection  in  general. 


239 


t 


MOTION  HEAD 

FART  III 
TALKING  PICTURES 

The  histrionic  stage  holds  a  mirror  up  to  nature.  That  is  the 
text  upon  which  a  preliminary  description  of  the  art  of  the  talking 
picture  will  be  based.  The  motion  picture  reproduces,  as  a  mirror 
would  reproduce,  the  histrionic  stage;  the  actors  of  the  drama  are 
voluble  of  lip  and  expressive  of  face  and  gesture,  but  they  are  silent. 
The  motion-picture  scene  of  the  waterfall  shows  the  tossing  waves 
and  the  plunging  masses  of  turbulent  water,  but  the  splash  of  the 
rapids  and  the  roar  of  the  cataract  are  not  heard.  In  the  motion  pic- 
ture of  the  rural  sunmier  landscape  the  trees  may  wave  their  boughs 
upon  the  picture  screen  and  the  atmosphere  of  the  grove  seems 
almost  to  pervade  the  theater,  but  the  murmur  of  the  breeze  in  the 
tree  tops  and  the  buzz  of  the  cicada  are  not  there. 

The  motion  picture  truly  holds  a  mirror  up  to  nature,  but  it  is 
only  an  ordinary  looking-glass  giving  back  the  scenes,  but  not 
the  sounds.  The  talking  picture  promises  nothing  new  from  the 
picture  screen,  but  promises  to  supply  the  missing  sounds,  to  couple 
the  senses  of  sight  and  hearing,  and  to  make  the  reproduction  of 
the  subject  complete,  at  least  so  far  as  drama  and  vaudeville  may 
be  concerned. 

NATURE  OF  THE  PROBLEM 

To  get  a  close  understanding  of  the  problem  of  the  talking 
picture  the  experimenter  may  assume  a  position  before  a  mirror, 
and,  being  in  such  position  in  fancy  or  in  fact,  he  may  talk,  sing, 
laugh,  or  dance  before  it.  If  he  should  talk  or  sing,  the  lip 
movements  would  be  reflected  by  the  mirror  exactly  as  produced 
by  his  lips.  These  movements  he  will  see  in  the  mirror.  At  the 
same  time,  he  will  hear  his  owti  voice,  but  not  in  the  mirror  or  from 
the  mirror.  If  he  should  dance,  the  faithfid  mirror  gives  back  every 
movement  to  his  -eye,  but  does  not  give  back  to  his  ear  the  sounds 
of  his  feet  upon  the  floor;  those  sounds  are  heard  by  his  ears  directly 

Copyright,  191 1,  by  American  School  of  Correspondence. 


241 


166  THE  MOTION  PICTURE 

Now  let  the  experimenter  bring  into  his  servnce  the  motographic 
camera.  Again,  he  may  talk,  sing,  laugh,  or  dance.  The  mirror 
is  replaced  by  the  sensitive  photographic  film,  which  receives  the 
lio-ht  much  as  the  mirror  did,  but  which  records  it  as  received.  By 
processes  of  photographic  development  and  printing  and  then  by 
projection,  the  motographic  film  is  made  to  give  its  record  to  vision, 
long  after  the  experimenter  has  ceased  talking,  singing,  laughing, 
or  dancing. 

AMiat  is  this  projected  motion  picture,  recorded  by  the  moto- 
graphic camera  and  the  sensitive  photographic  film?  Just  what  the 
mirror  gave  back — the  scene  but  not  the  sound.  The  photographic 
film  was  sensitive  to  light  but  not  to  sound,  and  recorded  light  but 
not  sound,  ultimately  reproducing  its  record  in  light  but  not  in  sound. 

Recording  Sound.  The  phonograph,  or  graphophone,  is  hardly 
older  than  the  motion-picture  camera.  Like  the  motion-picture 
camera,  the  graphophone  has  a  recording  surface  but  the  surface 
is  of  a  different  nature  and  the  method  of  recording  upon  it  is  differ- 
ent. The  camera  record  surface  makes  a  record  of  light;  the  grapho- 
phone record  surface  makes  a  record  of  sound.  Like  the  camera, 
the  graphophone  may  be  made  to  give  back  its  recorded  message 
in  the  language  of  the  record,  light  for  the  one  and  sound  for  the 
other. 

How  easy  it  seems  for  the  experimenter  to  procure  both  a  camera 
and  a  graphophone,  and  to  talk,  sing,  laugh,  or  dance  before  both 
of  them  and  then  have  both  of  them  reproduce  their  respective  records 
at  the  same  time,  whereby  not  only  the  sight  but  the  sound  of  the 
speech,  song,  laugh,  or  dance  may  be  reproduced  at  will  from  the 
inert  records  for  the  entertainment  of  the  experimenter  or  others. 
With  the  first  experiment  at  this  duplex  making  of  records,  the 
feature  of  synchronism  will  become  a  prominent  and  probably  an 
inharmonious   one. 

Synchronism.  When  the  experimenter  stood  before  the  mirror, 
he  heard  the  spoken  word  at  the  same  instant  that  he  saw  the  lips 
in  the  mirror  move.  He  heard  the  sound  of  the  step  of  the  dance 
at  the  same  instant  that  he  saw  the  mirrored  foot  strike  the  floor. 
But  in  the  reproduction,  such  a  difference!  The  graphophone 
begins  the  song  before  the  pictured  man  upon  the  screen  has  opened 
his  lips;  or  the  picture  shows  the  experimenter  singing  or  dancing 


242 


II 


MOTION  HEAD  167 

in  a  manner  familiar  to  all  theatergoers,  and  in  the  midst  of  the 
motion  picture  the  graphophone  begins  a  song  or  a  clatter  which 
seems  to  have  no  relation  to  the  picture.  Synchronism  is  lacking. 
The  experimenter  now  has  learned  that  liis  two  records  must  start 
together,  or  in  proper  relation,  and  must  keep  together,  for  when 
they  are  only  a  second  apart  in  time,  they  are  more  ludicrous  than 
when  so  far  separated  that  they  seem  to  have  no  relation  at  all. 

The  graphophone  has  not  been  perfected  for  the  minor  soimds 
of  nature.  The  human  voice  is  about  the  limit  for  the  sound  record. 
Voices  an^i~musical  instruments  are  the  standard  repertoire  of  the 
talking  machine,  other  records  being  the  exception  rather  than  the 
rule.  This  limitation  of  the  graphophone  limits  the  combination 
sight-and-sound  entertainment  to  dramatic  and  vaudeville  incidents, 
dancing  and  singing. 

The  tremendous  demand  for  motion  pictures  which  do  not  talk, 
the  large  number  of  theaters  projecting  motion  pictures  as  the  prin- 
cipal part  of  their  program,  and  the  avidity  with  which  the  theater 
manager  investigates  novelties  to  please  his  patrons,  all  indicate 
that  a  successfid  talking  picture  with  a  rehable  system  of  projection 
to  maintain  s\Tichronism  between  picture  and  speech  would  meet 
with  a  royal  welcome  and  bring  a  rich  reward  to  its  promoters. 
Thus  it  has  become  the  dream  of  inventors  to  combine  those  two 
devices,  the  motion  picture  and  the  graphophone,  successfidly,  but 
always  the  stumbling  block  has  been  synchronism. 

Not  only  must  the  picture  film  and  the  talking  record  be  capable 
of  synchronism,  but  means  must  be  provided  whereby  they  may 
be  kept  in  s\Tichronism  either  automatically  or  with  a  minimum 
amount  of  skill  on  the  part  of  the  theater  operators.  Synchronism, 
therefore,  must  be  considered  in  two  phases :  first,  making  the  photo- 
graphic record  and  the  sound  record  in  such  relation  that  reproduc- 
tion in  synchronism  is  possible,  and,  second,  reproducing  them  properly 
as  intended  in  their  manufacture. 

If  the  graphophone  record  and  the  picture  film  must  be  pro- 
jected at  the  same  speed  to  keep  them  in  unison  or  in  synchronism 
as  required,  may  not  both  be  put  in  a  single  machine  equipped  with 
sound  reproducer  and  a  projecting  lantern?  In  toys  this  is  practicable, 
or  in  a  home  exhil)ition,  but  in  a  large  theater  thejnotion  pictures 
are  projected  from  behind  the  audieiiCe,''passing  over  their  heads 


243 


168  THE  MICTION  PICTURE 

to  the  picture  screen  and  being  appreciated  by  the  audience  only  as 
rays  passing  from  the  screen  to  the  eye.  If  the  graphophone  were 
located  with  the  projecting  machine  for  the  pictures,  the  sound 
would  come  to  the  audience  from  l)ehind,  which  would  be  unnaturaL_ 


Instead,  the  sound  must  come  from  the  front  of  the  theater.  This 
limitation  compels  the  location  of  the  phonograph  at  or  near  the 
picture  screen,  while  the  projection  machine  must  be  at  the  back  of 
the   theater. 

Onlv  bv  projecting  the  pictures  upon  the  back  of  a  translucent 
curtain  and  permitting  the  graphophone  to  talk  through  the  cur- 
tain may  the  two  devices  be  located  together. 

The  two  machines,  motion-picture  projector  behind  the  audience 
and  graphophone  in  front  of  the  audience,  may  be  kept  together 
in  speed  bv  some  relation  of  propelling  or  controlling  means.  It  is 
in  this  feature  that  inventors  have  beeu  most  active,  and  it  is  in  this 
feature  that  the  differences  will  be  found  in  analyzing  and  comparing 
,'^'the  different  "talking  picture"  machines  and  systems  offered  and  to 
be  offered  upon   the  market. 

Length  of  Records.  Theoretically,  there  are  no  limitations  of 
length  of  a  talking  picture,  for  the  second  talking  machine  may  be 
started  just  as  the  first  talking  machine  is  stopped,  and  the  third 
disk  of  the  series  may  be  placed  upon  the  first  talking  machine  to  be 
started  just  as  the  second  one  has  stopped.  Likewise,  with  two  pro- 
jecting machines,  the  second  reel  of  film  may  be  started  just  as  the 
first  is  stopped,  and  the  first  projecting  machine  then  may  take  up 
the  third  reel  just  as  the  second  is  finished. 

With  a  single  talking  machine  and  a  single  projecting  machine, 
the  limit  is  reached  with  the  talking  machine  first.  The  maximum 
talking  record  m^America  is^  thei^^iTrdrTiiskrTTiTtniiig  fixajninutes. 
The  10-inch  disk  runs  three  to  four  minutes,  while  the  "four-minute" 
cylinder  record  lives  up  to  its  name,  running  four  minutes  or  longer. 
European  records  running  fifteen  to  twenty  minuj;es  have  been 
reported  and  will  be  of  value  in  the  talking-picture  art  when  adopt- 
ed for  that  purpose.  Cinephone  films  are  offered  upon  10-inch  disk 
records,  each  accompanied  by"  loO  to  2.')0  feet  of  motion-picture  film. 

The  possibility  of  the  longer  talking  picture  is  assured,  for  it 
has  been  done.  As  for  long,  continuous  sound  records  upon  a  num- 
ber of  disks,  there  are  already  offered  to  the  general  public  for  use 


244 


II 


MOTION  HEAD  169 

in  private  talking  machines,  records  for_the  compIet£__Qperas  of 
"Faust"  and  "William  Tell."  These  records  may  have  motion 
pictures  fitted  to  them,  according  to  the  methods  of  the  manufacture 
of  talking  pictures,  or  records  of  equal  length  may  be  made  from 
the  same  or  other  subjects,  complete  with  picture  films. 

CLASSIFICATION 

All  of  the  suggestions  as  yet  made  for  producing  talking  pic- 
tures may  be  brought  under  one  of  the  following  three  classes: 

(/)  The  two  machines  are  driven  from  the  same  source  of 
power  and  are  so  related  to  this  source  that  their  speed  of  reproduc- 
tion is  identical. 

(2)  The  two  machines  are  so  related  that  one  drives  the  other 
or  controls  the  speed  of  the  other  directly. 

(J)  Index  hands  or  the  equivalent  are  provided  for  the  two 
machines,  and  an  attendant,  by  constant  supervision,  keeps  these 
index  hands  in  proper  relation. 

(1)  Unitary  Machines.  In  the  unitary  machine,  the  two 
machines,  projector  and  graphophone,  are  built  together  and  are 
driven  by  the  same  main  shaft  of  the  combined  machine,  which  may 
be  turned  by  a  crank  or  motor  of  any  kind.  In  such  a  device,  it  is 
necessary  to  be  able  to  secure  exact  synchronism  at  the  starting  of 
the  picture  and  sound  records,  or  to  provide  some  means  of  adjust- 
ing in  order  to  enable  the  operator  in  charge  to  get  his  picture  to 
catch  up  with  his  graphophone,  or  to  permit  his  picture  to  slow  down 
to  let  the  graphophone  catch  up  with  the  picture. 

Long  Main  Shaft.  An  invention  which  places  two  machines 
in  the  first  class  is  the  system  of  providing  a  long  main  drive  shaft 
under  the  floor  of  the  theater,  gearing  it  at  one  end  to  the  graphophone 
and  at  the  other  end  to  the  projecting  machine.  At  the  projecting 
machine  end,  a  clutch  should  be  provided,  and  if  the  start  is  not 
made  in  synchronism,  so  that  an  adjustment  is  required,  the  operator 
may  throw  out  the  clutch  and  turn  the  projector  l)y  hand  faster  or 
slower  until  he  gets  the  picture  in  synchronism  with  the  speaking 
record;  then  he  may  throw  in  the  clutch  again,  and  the  main  shaft, 
driven  by  a  constant-speed  motor  of  sufficient  power,  keeps  the  two 
machines  in  constant  speed  relation,  projecting  their  two  records 
at  the  same  speed  and  in  synchronism. 


245 


170 


THE  MOTION  PICTURE 


^Mien  a  splice  in  the  film  passes,  where  a  few  images  have  been 
cut  from  the  film  in  repairing  it,  the  picture  film  wilLrun^ead  of 
the  graphophone  record  and  the  operator  must  detach  his  projector 
from  the  main  drive  shaft  until  the  two  records  are  brought  into 
synchronism  again.  A  new  film  should  run  in  synchronism  from 
start  to  finish  under  this  method  of  driving,  but  an  old  film  which 
has  many  breaks  and  splices  becomes  harder  and  harder  to  operate 


Fig.  105.     The  Photophoue.      A  Unitary  Talking- Picture  Machine 

in  synchronism  as  its  splices  increase.  A  matter  of  three  to  six  pic- 
tures cut  from  the  film— one-fifth  to  two-fifths  of  a  second  in  time  of 
projection — is  sufficient  in  most  talking-picture  records  to  render 
them  very  noticeably  out  of  synchronism. 

Synchronous  Electric  Motors.  There  is  an  electric  motor  which 
is  called  a  synchronous  motor  because  when  carrying  its  load  it  runs 
always  in  exact  accordance  with  the  speed  of  the  d}Tiamo  which  is 
furnishing  the  electric  current  for  driving  the  motor.  It  is  a  motor 
operated  by  an  alternating  current,  and  its  speed  always  is  propor- 
tional to  the  speed  rapidity  or  frequency  of  alternation  of  the  current 
which  drives  it.     When  two  such  motors,  just  alike,  are  placed  in 


246 


MOTION  HEAD  171 

service  upon  the  sjime  power  circuit,  driven  by  alternating  current 
from  the  same  central  station  electric  dynamo,  it  follows  that  each 
will  run  at  exactly  the  speed  of  the  other.  With  one  such  motor 
driving  the  graphophone  and  another  upon  the  same  power  mains 
driving  the  projecting  machine,  the  speed  of  the  record  of  the  grapho- 
phone and  projecting  machine  will  be  identical,  proper  speed  gear- 
ing to  the  motors  being  provided.  Any  slight  change  in  speed  of  the 
electric  generator  at  the  power  station  which  is  supplying  the  current 
for  the  motors,  which  of  course  would  result  in  a  slight  change  in 
the  frequency  of  the  current  upon  the  power  mains,  is  equally  effective 
upon  both  the  graphophone  and  the  projecting  machine,  so  that  th^i 
two  machines  always  move  in  unison,  keeping  the  reproductions  of 
their  records  in  synchronism,  if  the  records  have  been  made  properly. 

Illustration.  In  the  unitary  machine,  shown  in  Fig.  105,  the 
motion  head  of  the  projector  portion  of  the  apparatus  is  built  upon 
the  support  for  the  graphophone  horn.  The  moving  parts  of  the 
motion  head  are  driven  from  the  graphophone  motor  which  turns 
the  flat  disk  record  under  the  reproducing  needle  of  the  talking 
machine.  It  is  necessary  only  to  set  the  graphophone  needle  to  a 
marked  point  upon  the  talking  record  disk  and  to  luring  a  marked 
picture  image  into  the  film  window  of  the  motion  head,  then  start 
the    motor. 

To  produce  a  compact  combination  device  without  permitting 
the  horn  of  the  phonograph  to  interfere  with  the  beam  of  light  of 
the  projected  picture,  the  lenses  are  arranged  to  project  the  pic- 
ture through  the  horn,  as  shown  in  Fig.  105. 

In  this  device  if  the  motion  head  be  disconnected  from  the 
graphophone  motor,  a  crank  may  be  attached  to  the  motion  head 
and  the  skill  of  the  operator  then  may  attain  and  maintain  a  synchron- 
ism which  approaches  pei-fection  only  by  the  degree  of  skill  of  the 
operator. 

Two  machines  driven  by  the  same  source  of  power  are  shown 
in  Fig.  106.  The  source  of  power  in  this  instance  is  the  operator's 
arm  turning  the  crank  in  the  projection  room  at  the  upper  left- 
hand  comer  of  the  figure.  The  crank  is  attached  to  one  of  a  pair  of 
bevel  gears  in  the  operating  room,  and  thus  drives  the  vertical  rod 
extending  down  through  the  floor  of  the  operating  room  to  a  point 
below  the  floor  of  the  theater.    There,  it  transmits  its  power  to  the 


247 


172 


THE  MOTION  PICTURE 


long  horizontal  main  shaft  extending  under  the  floor  of  the  theater 
to  a  point  under  the  graphophone.  The  graphophone  takes  its 
power  from  this  long  horizontal  shaft  by  means  of  a  short  connecting 
vertical  shaft.  Thus  the  projecting  machine  and  the  graphophone 
are  driven  by  the  same  crank  through  an  arrangement  of  gear  wheels 
and  shafts. 

Any  variation  in  the  speed  of  the  graphophone  will  change  the 
pitch  of  the  sounds  being  produced^  a  result  which  cannot  be  per- 
mitted in  reproducing  musical  records,  and  which  woiild  be  very 


Fig.  106.     Talking  Picture  Reproduction  by  Two  Reproducers  Driven  from  a  Long 

Power  Shaft 

objectionable  in  any  sound  record.  On  the  other  hand,  the  motion 
pictures  must  be  projected  at  about  the  speed  for  vVhich  they  were 
intended  when  made.  This  distinction  exists,  however,  that  while 
a  small  variation  may  be  permitted  in  the  speed  of  the  motion  pic- 
tures, no  variation  at  all  should  be  permitted  in  the  speed  of  the 
graphophone  reproduction.  Hence,  the  graphophone  must  be  driven 
at  a  speed  as  nearly  constant  as  can  be  obtained  by  an  acceptable 
motor,  and  the  speed  of  the  motion  picture  must  be  varied  to  bring 
the  two  reproductions  together  whenever  for  any  reason  or  by  any 
aci'ident  they  lose  their  relation  of  synchronism. 

A  splice  upon  an  injured  film  will  cut  out  a  few  images.    When- 
ever this  .splice  in  the  film  passes  through  the  motion  head,  the  motion- 


248 


MOTION  HEAD 


173 


picture  film  will  begin  to  project  its  picture  record  ahead  of  the 
sounds  from-the-^aphophone,  and  the  projector  must  be  slowed 
down  in  speed  until  the  graphophone  catches  up.  Should  the  grapho- 
phone  needle  "jump  a  thread"  or  Ijy  any  accident  or  a  defect  in  the, 
record  fail-to  follow  the  record  accurately,  the  projection  operator 
must  turn  the  projector  faster  or  slower  to  vary  the  speed  of  the* 
motion  picture  until  the  two  records 
again  are  being  produced  in  synchro- 
nism. It  will  be  seen  that  in  Fig.  106, 
to  adapt  the  arrangement  to  practical 
work  in  a  theater,  the  handle  must  be 
geared  permanently  to  the  shafting,  and 
the  motion  head,  of  the  projection  ma- 
chine must  have  such  a  relation  that  it 
may  nm  slower  or  faster  in  order  to  be 
capable  of  adjustment  for  synchronism. 

{2)  Dependent  Machines.  In  this 
class  of  reproducing  mechanisms  for 
talking  pictures,  one  machine  must 
drive  the  other,  or  must  control  the 
other.  As  the  variation  in  speed  due 
to  control,  if  any,  must  be  impressed 
upon  the  picture  projector  and  not  upon 
the  graphophone,  the  problem  resolves 
itself  into  a  constantly-driven  grapho- 
phone either  driving  or  controlling  the 
picture  projecting  machine.  Such  a 
pair  of  dependent  machines  is  shown 
in  Figs.  107  and  108,  the  former  show- 
ing the  graphophone,   and    the   latter,  the  picture  projector  motor. 

The  machine  illustrated  is  one  brought  out  in  Paris  and  in- 
vented by  Captain  Couade.  Thq  crank  seen  in  Fig.  107  is  the  crank 
for  winding  up  the  motor  of  the  graphophone,  and  not  for  turning 
the  graphophone  directly.  This  graphophone  runs  in  the  usual 
manner,  and  may  be  quite  an  ordinary  type  of  talking  machine, 
with  the  addition  of  a  commutator  for  electric  current  which  changes 
a  constant  potential  to  a  system  of  intermittent  potentials  upon 
different  circuits,  the  relation  of  the  potentials  produced  by  the  com- 


FiK.  107.  Graphophone  for 
Talking  -  Pictiu'e  Reproduction, 
Sending  Current  to  Distant  Pro- 
jecting Motor  through  Electric 
Cable  , , 


249 


174 


THE  MOTION  PICTURE 


mutators  of  the  graphophone  being  likened  to  the  related  potentials 
of  a  three-phase  alternating  current.  The  electric  commutator  is 
inside  the  graphophone  cabinet,  the  electric  terminals  and  switches 
being  seen  in  the  figure  upon  the  outside  of  the  cabinet.  The  wires 
which  lead  from  the  graphophone  downward  carry  the  electric 
potential  impulses  created  by  the  graphophone  commutator.  In 
Fig.  108  is  shoTsii  the  motor  for  driving  the  motion-picture  projec- 


Flg.  108.     Motor  for  Picture- Projecting  Machine  for  Talking 

Pictures,  Driven  in  Sj-nchronism  with  the  Grapliophone 

by  Current  Received  Over  an  Electric  Cable 

tion  machine.  This  figure  does  not  show  the  projection  machine, 
nor  is  it  necessary  to  do  so,  since  any  projection  machine  may  be 
used  to  project  the  picture  film,  provided  only  it  is  coupled  to  this 
special  motor  and  driven  by  that  motor  at  exactly  the  speed  which 
the  graphophone  dictates  by  means  of  its  electric  commutator.  The 
electric  cable  rising  from  the  bottom  of  P'ig.  108  to  terminals  upon 
the  side  of  the  motor  is  connected  at  its  other  end  with  the  commutator 
of  the  distant  graphophone,  located  near  the  picture  screen  of  the 
theater. 


S50 


MOTION  HEAD  175 

In  operation,  the  motion-picture  film  is  placed  in  the  film  gate 
and  framed  with  a  marked  image  in  the  film  window.  The  needle  of 
the  graphophone  then  is  placed  upon  the  record  disk  at  a  marked 
point.  These  two  marked  points,  one  on  the  picture  film  and  one 
on  the  sound  record,  were  obtained  in  manufacture  and  placed 
upon  the  records  when  the  records  were  made.  They  are  points  to 
which  the  records  are  in  unison  in  time  with  reference  to  the  light 
and.  sound  of  the  subject. 

The  phonograph  now  is  started  and  dri^■en  in  the  usual  manner. 
The  motion  head  of  the  projection  machine,  driven  by  the  motor, 
gains  speed  as  the  phonograph  gains  speed,  until  both  are  running 
fully.  If  the  projection  machine  is  provided  with  an  automatic  fire 
shutter,  the  shutter  will  be  lifted  and  permit  the  projection  of  the 
picture  upon  the  screen  as  soon  as  sufficient  speed  has  been  attained. 

In  this  device,  the  motion-picture  projector  is  started  by  the 
graphophone,  and  it  is  run  with  the  graphophone,  stopping  with 
the  graphophone.  The  power  for  running  the  motion-picture  pro- 
jector is  not  created  by  the  graphophone,  nor  by  its  motor,  but  it  is 
so  controlled  by  the  commutator  of  the  graphophone  as  to  drive  the 
motor  and  the  picture  machine  at  the  required  speed.  The  motor 
is  so  constructed  as  to  be  unable  to  turn  under  the  influence  of  any 
direct  current  which  may  leak  to  it  through  the  graphophone  com- 
mutator while  the  graphophone  is  at  rest.  The  operator  at  the  pro- 
jection machine  must  note  any  lack  of  synchronism  and  correct  it, 
after  v.^hich  the  records  will  stay  together. 

(3)  Dial=Regulated  Machines.  In  this  class  of  reproducing 
devices  for  talking  pictures,  the  talking  machine  and  the  picture 
machine  are  separate,  and  each  has  an  index  hand.  The  index 
hands  need  have  no  direct  relation  to  each  other  nor  any  direct 
connection  with  each  other,  but  each  serves  to  show  the  speed  at 
which  its  associated  machine  is  being  driven.  The  graphophone 
being  driven  at  a  constant  speed,  its  index  hand  will  revolve  at  a 
constant  speed,  and  the  projection  machine  operator  then  nuist 
turn  his  crank  at  such  speed  as  will  make  the  picture  machine  index 
hand  keep  up  with  the  pace  of  the  graphophone  hand,  and  not  run 
ahead  of  it. 

Greenbaum.  In  Fig.  109  is  shown  a  diagram  of  the  system  and 
some  detail  of  the  apparatus  of  the  Greenbaum  device.    In  the  figure, 


231 


176 


THE  MOTION  PICTURE 


at  the  upper  left-hand  comer,  is  shown  a  commutator  upon  a  shaft 
which  is  mounted  in  connection  with  the  shaft  of  the  motion-picture 
projector.  At  the  upper  right-hand  corner  of  the  figure  is  shown  a 
similar  commutator  which  is  mounted  upon  a  revolving  shaft  which 
is  associated  with  a  shaft  of  the  graphophone.    The  device  forming 


Fig.  109.     Greenbaum  Mechani.sm  for  Synchronizing 
Talking  Picture 

the  lower  part  of  the  figure  is  a  dial  which  is  mounted  in  the  operat- 
ing room,  in  front  of  the  operator  who  is  turning  the  crank  of  the 
inotion-j)icture  projector.  Upon  the  dial  are  seen  two  index  hands, 
24  and  29.  The  hand  2^  is  driven  by  the  picture  projector  and  the 
hand  29  is  driven  by  the  graphophone.     When  the  two  machines 


252 


MOTION  HEAD  177 

are  running  in  synchronism,  the  two  hands  will  maintain  a  constant 
angle  between  them,  preferably  being  together,  that  is,  the  hand  ^4 
should  cover  the  hand  29.  By  reason  of  splices  in  the  film,  or  by  ac- 
cident, the  hands  may  become  separated,  in  which  case  the  angle  be- 
tween them  must  be  kept  constant  by  the  projection-machine  operator. 

Electric  incandescent  lamps  also  are  provided — as  shown  by 
the  circles  50,  51,  and  52  in  the  figure — and  are  so  arranged  that 
lamp  51  will  glow  when  pictures  and  talking  record  are  in  unison; 
lamp  52  will  glow  if  the  pictures  are  behind  time;  and  lamp  50  will 
glow  if  the  pictures  are  ahead  of  the  talking  record.  The  lamps,  as 
well  as  the  hands,  serve  to  guide  the  projecting  operator  to  keep  the 
two  records  in  synchronism. 

The  mechanical  arrangement  of  parts  in  the  Greenbaum  device 
is  as  follows:  In  the  case  1,  the  two  electromagnets  2  and  3  are 
mounted.  Electromagnet  2  is  connected  by  electric  wires  12  with 
the  electric  commutator  device  of  the  shaft  ^  pertaining  to  the  pro- 
jector, in  such  manner  that  every  time  the  commutator  of  the  shaft 
4  closes  the  electric  circuit  an  impulse  of  electric  current  will  flow 
from  the  battery  A  through  the  wires  12  and  the  commutator  and 
the  magnet  2  to  cause  the  armature  10  of  the  magnet  12  to  be  attracted. 
This,  by  the  action  of  the  pawl  17,  drags  the  ratchet  wheel  IS  down 
one  tooth;  this  ratchet  wheel  in  turn  by  a  pair  of  gear  wheels  drives 
the  shaft  of  the  hand  24,  moving  the  hand  2Jf  a  short  step  over  the 
dial  30.  One  such  step  of  the  hand  ^4  i^  made  for  each  revolution 
of  the  shaft  4  of  the  projector,  hence  the  speed  of  the  movement  of 
the  hand  2Jf  is  a  measure  of  the  speed  of  the  projector. 

In  like  manner,  electromagnet  3  is  connected  by  electric  wires 
IJf  and  15  with  the  electric  commutator  device  of  the  shaft  8,  per- 
taining to  the  talking  machine,  in  such  manner  that  every  time  the 
commutator  of  the  shaft  8  closes  the  circuit  an  electric  impulse  will 
flow  from  the  battery  B  through  the  wires  I4.  and  15  and  the  com- 
mutator and  the  magnet  3  to  cause  the  armature  16  of  the  magnet 
3  to  be  attracted.  This  by  the  action  of  the  pawl  17  drags  the  ratchet 
wheel  19  up  one  tooth;  this  ratchet  wheel  in  turn  by  a  pair  of  gear 
wheels  turns  the  tubular  shaft  of  the  hand  19,  moving:  the  hand  29 
a  short  step  over  the  dial  30.  The  hands  24  and  29  move  in  the  same 
angular  direction,  and  when  the  records  are  being  rendered  in  unison 
they  move  at  the  same  speed. 


253 


178  THE  MOTION  PICTURE 

It  is  necessary,  in  starting  the  devices  to  render  a  talking  pic- 
ture, to  place  the  film  in  the  motion  head  with  a  marked  image  in 
the  film  window,  to  place  the  needle  of  the  talking  machine  upon 
a  marked  place  in  the  record,  then  to  place  the  two  hands  of  the 
indicator  together.  After  that,  if  the  hands  are  kept  together,  the 
records  will  be  kept  together  as  the  records  are  reproduced.  The 
passing  of  splices  where  images  have  been  cut  from  the  picture  film 
will  cause  the  hands  to  separate  if  sjTichronism  is  maintained  by 
the  operator,  since  the  projection  operator  must  slow  down  his 
machine  to  regain  synchronism,  after  which  the  relation  of  the  hands 
is  maintained  at  the  new  angle. 

Cinephone.  The  cinephone  system  of  talking-picture  produc- 
tion will  appeal  alike  to  the  projection  operator  and  to  the  practical 
theater  manager,  and  for  the  same  reason,  namely,  that  it  has  a 
minimum  of  special  apparatus  in  the  theater,  and  it  requires  the 
least  specialization  of  skill  on  the  part  of  the  projection  operator. 

The  cinephone  as  offered  to  the  public  is  in  substance  only  an 
attachment  for  a  well-known  type  of  talking  machine.  As  built  it  is 
a  quick-starting  talking  machine  having  an  unusually  heavy  spring 
which  permits  it  to  obtain  its  full  speed  and  volume  of  sound  almost 
instantly  upon  the  release  of  the  ordinary  brake  which  sets  the  disk 
record  revolving.  It  may  be  used  for  ordinary  disk  records  for  enter- 
tainment between  pictures,  or  for  illustrated  songs,  without  the 
cinephone  motion-picture  films,  which  in  connection  with  the  talk- 
ing machine  produce  the  talking  pictures. 

The  cinephone  talking  machine  stands  at  the  side  of  the  picture 
screen  and  faces  the  audience  and  the  projection  operator.  It  has 
an  illuminated  dial  upon  its  front  face,  upon  which  there  is  an  illu- 
minated revolving  hand.  The  course  of  the  hand  is  marked  by  four 
green  bullseye  lamps,  readily  discernible  by  the  projection  operator 
in  a  darkened  auditorium,  even  at  a  distance  of  two  hundred  feet. 

The  illuminated  dial  and  hand  are  for  the  purpose  of  register- 
ing the  exact  speed  at  which  the  talking  machine  is  operated.  A 
similar  dial  and  hand  are  photographed  into  the  motion-picture 
film,  the  hand  of  the  motion-picture  film  traveling  over  a  circle  which 
is  marked  by  four  white  bullseye  spots  upon  the  picture  screen.  This 
second  dial  and  hand  appear  in  the  lower  left-hand  corner  of  the  film 
picture  and  of  the  screen  when  the  picture  is  projected  upon  it. 


254 


MOTION  HEAD  179 

As  the  picture  is  shown,  the  dial  hand  in  the  screen  and  the 
dial  hand  upon  the  front  of  the  talking  machine  both  move  in  the 
same  direction  and  at  the  same  speed.  The  projection  machine  is 
operated  at  a  speed  calculated  to  keep  both  dial  hands  at  the  same 
point  upon  the  dial  circumferences  at  all  times.  So  simple  is  this, 
that  anyone  can  be  taught  to  produce  cinephone  synchronism  in  a 
few  moments. 

Any  projection  machine  already  in  use  may  be  used  under  this 
system  of  synchronism  and  any  ordinary  operator  can  master  the 
additional  detail  quickly  and  show  a  finished  talking  picture. 

There  are  no  connections,  electrical  or  otherwise,  between  the 
cinephone  talking  machine  and  the  picture  screen,  nor  between  the 
cinephone  talking  machine  and  the  projection  machine.  The 
operators  required  are  the  projection-machine  operator  and  the 
pianist  or  other  musician  or  regular  attendant  of  the  theater  to  make 
the  change  of  records  and  rewind  the  talking-machine  motor,  and 
to  start  the  talking  machine  when  the  starting  flash  is  received  from 
the  picture  projector.  It  is  the  intention  of  cinephone  design  that 
the  number  of  employes  of  the  theater  need  not  be  increased,  and 
that  no  special  skill  be  required  of  any  of  them. 

MANUFACTURE 

The  theoretical  method  of  recording  action  and  speech,  by 
locating  a  recording  graphophone  and  a  motion-picture  camera 
properly  near  the  speaking  actor,  has  limitations.  The  graphophone 
must  be  near  the  spe^er,  or  it  will  not  record  the  speech,  while  the 
camera  requires  some  intervening  disj^^ance  in.9j:der-.to-;se€ure  a  -proper 
rendering  of  _tlie--pietTiTeI  ^et  the  graphophone  must  not  appear  as  '\ 
an  object  in  the  picture  obtained  by  the  camera. 

Small  Subjects.  A  very  delightful  and  thoroughly  successful 
talking  picture,  or  better  "singing"  picture,  is  that  of  a  canary-bird 
singing  in  its  cage.  The  actual  area  pictured  by  the  camera  is  only 
about  a  scjuare  yard,  with  the  bird  near  the  center,  so  that  the  grapho- 
phone recording  horn  could  be  brought  within  18  inches  of  the  bird 
without  appearing  in  the  picture  made  by  the  camera.  In  this  man- 
ner, the  two  records  could  be  made  simultaneously,  and  when  repro- 
duced they  are  capable  of  absolute  unison  when  properly  synchronized 
and  uniformly  driven  at  the  proper  speed. 


255 


180 


THE  AMOTION  PICTURE 


A  talking  picture  of  a  "laugh"  in  which  the  laughing  face  is 
taken  by,  the  camera  afcTose^range,  to  fill  the  entire  space  of  the  pic- 
ture image,  being  then  projected  to  fill  the  entire  picture  screen, 
may  be  made  in  the  same  manner.  Even  in  the  case  of  a  monologue 
by  a  single  actor,  where  the  actor  standing  before  the  camera  fills 
the  picture  image  space  to  the  top  line,  the  limit  of  the  field  of  the 
camera  may  be  determined  very  accurately  and  the  recording  grapho- 


Fig.   110.     Producing  the  Talking  Record  for  a  Talking  Picture 

phone  horn  may  be  j)laced  just  above  the  limit  of  vision,  that  is,  just 
above  the  picture  as  projected  upon  the  screen. 

Large  Subjects.  In  producing  a  talking  picture  where  several 
actors  are  involved,  the  method  of  manufacture  is  to  make  the  talking 
record  first,  and  then  fit  a  motion  picfuf e~to  it^  To ^J«  this,  the  actors 
are  well  drilled  in  their  parts,  so  that  they  will  be  able  to  produce  the 
performance  twice,  once  in  sound  for  the  sound  record  and  once  in 
action  for  the  picture  record. 

The  actors  being  thus  trained,  the  sound  record  is  produced 
without  any  reference  to  what  the  appearance  of  the  actors  may  be 
while  producing  the  record,  the  end  desired  being  only  that  the  best 
po-ssible  sound  record  be  obtained. 


256 


MOTION  HEAD 


181 


A  group  of  actors  producing  a  sound  record  is  shown  in  Fig.  1 10. 
They  are  standing  compactly  grouped,  facing  the  recording  grapho- 
phone.  The  stage  director  stands  coatless  above  them.  In  Fig.  Ill, 
the  next  step  of  the  process  is  shown,  namely,  that  of  training  the 
actors  into  unison  with  the  sound  record  alreatly  produced.  In  the 
foreground  is  seen  the  horn  on  the  talking  machine.  It  is  rendering 
the  sound  record.  Before  the  horn  stand  the  stage  director  and  a 
group  of  the  actors.    The  actors  are  repeating  the  words  which  they 


Fig.   111.     Drilling  the  Actors  before  the  Graphophone  to  Attain  Unison  with  the 
Talking  Record  before  Making  the  Picture  Record  of  a  Talking  Picture 

used  in  making  the  sound  record,  repeating  them  in  unison  with 
the  talking  marhtiie,  and  at  the  same  time  suiting  the  actions  to  the 
words.  As  yet  the  camera  has  not  been  brought  into  use,  for  the  sound 
record  may  be  made  indoors,  and  the  rehearsal  for  action  may  be' 
made  indoors  as  well,  but  the  making  of  the  picture  must  be  done 
in  the  field  before  a  suitable  background  or  in  the  studio  in  a  proper 
stage  setting. 

Talking=Picture  Camera.  The  combination  camera  and  talk- 
ing machine  for  the  final  step,  namely,  the  making  of  the  picture 
record,  to  fit  the  talking  record,  is  shown  in  Fig.  112.  At  the  left  is 
the  reproducing  graphophone;  at  the   right  is   the  motion-picture 


257 


182 


THE  MOTION  PICTURE 


camera.  Both  are  mounted  upon  tripods,  for  use  in  field  or  studio. 
Connecting  the  two  machines  is  a  driving  shaft,  and  upon  the  tripod 
with  the  camera  is  mounted  an  electric  motor  for  driving  the  shaft. 
This  combination  machine  is  started,  the  actors  act  and  speak  in 
unison  with  the  talking  machine,  and  are  photographed  by  the 
camera.  Even  the  words  of  the  talking  machine  must  be  repeated 
in  unison  with  the  machine,  that  the  lip  movements  of  the  actor 
in  the  motion  picture  may  be  synchronous  with  the  spoken  words 
of  the  talking  machine. 

The  photographic  negative  is  developed  and  prints  are  made. 
The  starting  point  now  is  marked  upon  the  sound  record  and  upon 


Fig.  112.     The  Rerordins  Motion-Picture  Camera  Coupled  to  the 

Reprotlucius  Grapliophone  for  Producing  the  Picture 

Record  of  a  Talking  Picture 

the  picture  film,  and  the  two  records  are  ready  for  delivery  to  the 
theaters  for  tlie  production  of  talking  pictures. 

REPRODUCTION  OF  TALKING  PICTURES 

Operation  of  the  Cinephone.  The  picture  screen  and  talking 
machine  of  a  theater  with  the  cinephone  in  operation  are  shown  in 
Fig.  11. 'j.  Note  the  dial  upon  the  talking  machine,  and  the  similar 
dial  ill  the  lower  left-hand  corner  of  the  picture  upon  the  screen.    Note 


258 


I 


184  THE  IMOTIOX  PICTURE 

also  that  the  hands  upon  the  two  dials  occupy  the  same  relative 
positions. 

Starting  in  Synchronism.  The  pianist  assists  the  projection 
operator  by  managing  the  talking  machine.  The  talking  machine 
is  turned  slowly  by  the  motor  or  by  hand  until  the  index  hand  is  in 
an  upright  position,  pointing  to  the  top  lamp  of  the  four  which  sur- 
round its  dial  and  which  appear  in  Fig.  113  as  four  black  spots, 
above,  below,  to  the  right,  and  to  the  left,  respectively,  of  the  dial 
on  the  front  of  the  talking  machine.  The  disk  record  then  is  placed 
on  the  carrier  with  its  marked  point  under  the  needle.  A  groove  is 
cut  in  the  disk  to  guide  the  needle  to  the  starting  point  of  the  record. 
The  motor  of  the  talking  machine  is  wound  and  the  talking  machine 
is  ready  for  action. 

During  this  process,  a  small  incandescent  lamp  has  been  burning 
upon  the  top  of  the  talking  macliine;  when  all  is  in  readiness,  this  lamp 
is  turned  out  by  the  pianist  as  a  signal  to  the  projection  operator  in 
the  operating  booth  that  the  talking  machine  is  in  readiness. 

The  projection  operator  threads  his  leader  through  his  motion 
head  in  the  usual  manner,  there  being  no  special  marked  points  to 
be  observed,  and  begins  projecting  the  film  at  the  cinephone  speed 
of  eighteen  pictures  per  second,  or  about  sixty-six  feet  per  minute — 
a  speed  one-third  greater  than  the  usual  picture  speed.  All  initial 
leader  and  title  having  passed,  and  the  portion  of  the  picture  having 
been  reached  where  the  talking  machine  is  required,  there  appears 
upon  the  picture  screen,  for  a  fraction  of  a  second  only,  the  words, 
'  The  Cinephone."  This  is  the  "starting  flash,"  usually  stained  yel- 
low and,  therefore,  called  the  "yellow  flash,"  which  is  the  signal 
for  starting  the  talking  machine.  The  pianist,  who  has  been  wait- 
ing with  hand  on  starting  brake  of  the  talking  machine,  draws  the 
Ijrake  away  from  the  record  carrier. 

The  talking  machine  starts  at  full  speed,  and  the  index  hand 
of  the  talking  machine  also  starts  revolving.  At  the  time  of  the 
starting  flash,  the  index  hand  of  the  picture  film  is  vertical — note  the 
lower  left-hand  corner  of  Fig.  113 — and  so  corresponds  with  the 
vertical  position  of  the  index  hand  of  the  talking  machine. 

yiaintaiiring  Synchronism.  The  operator  turns  the  projecting 
machine  at  the  proper  speed  to  keep  the  two  index  hands  together, 
and  the  two  records  will  remain  in  synchronism  through  the  entire 


260 


MOTION  HEAD 


185 


picture.  The  cinephone  speed  is  faster 
than  the  ordinary  picture  speed,  the 
cinephone  film  running  fifteen  minutes  to 
the  reel  while  the  ordinary  film  nms  twenty 
minutes  to  the  reel,  but  the  ordinary  pro- 
jecting machine  will  stand  successfully  the 
strain  of  the  somewhat  higher  speed. 

The  index  hand  for  the  picture  screen 
dial  is  photographed  into  the  cinephone 
picture  film,  and  requires  nothing  special 
upon  the  projection  machine  for  the  pro- 
jection of  the  index  hand.  Splices  are  self- 
correcting  in  the  cinephone  film,  because 
when  a  few  images  are  cut  out  of  a  strip 
of  film,  the  index  hand  for  those  images  is 
cut  out  also. 

The  index  hand  makes  one  revolution 
upon  the  picture  screen  for  every  14  feet  of 
picture  film.  This  gives  the  hand  a  speed 
of  revolution  of  about  four  and  three- 
quarters  turns  per  minute,  or  one  turn  in 
about  thirteen  seconds,  the  talking-machine 
hand  having  the  same  speed  also.  If,  by 
some  accident,  the  projection  operator  is 
compelled  to  cut  out  a  piece  of  cinephone 
film,  say  even  as  much  as  3  feet  of  it,  the 
splicing  of  the  film  will  cause  a  jump  in  the 
pictures  which  will  take  them  out  of  syn- 
chronism with  the  talking  machine.  In 
such  a  case,  the  index  hand  upon  the  picture 
screen  will  appear  to  jump  also,  just  the 
same  as  any  other  moving  object  upon  the 
picture  screen.  For  a  3-foot  loss  of  film, 
the  index  hand  will  jump  a  quarter  of  a 
revolution,  and  be  a  quarter  turn  ahead  of 
the  calking-machine  index  hand ;  the  projec- 
tion operator  then  slows  down  his  motion 
head  until  the  talking-machine  hand  catches 


114.     A  Specimen  of 
Cinephone  Film 


261 


180  THE  MOTION  PICTURE 

up  for  the  loss,  and  witliin  ten  seconds  the  synchronism  will  be  re- 
stored for  the  loss  of  a  yard  of  film.  Ordinary  splices,  where  but 
from  one  to  six  of  the  little  pictures  are  lost,  pass  without  notice, 
beincf  almost  instantly  and  unconsciously  corrected  by  the  operator, 
whose  eye  is  constantly  upon  the  two  hands. 

In  case  the  talking  machine,  because  of  a  defective  machine, 
a  defective  needle,  or  a  defective  record,  should  "jump  a  thread," 
the  projection  operator  will  notice  it,  turning  either  faster  or  slower 
until  synchronism  is  attained  by  letting  the  index  hands  separate, 
then  turning  at  the  standard  speed  until  the  end  of  the  picture,  keep- 
ing the  index  hands  steadily  apart  at  the  distance  caused  by  the  loss 
or  gain  of  the  talking  machine.  With  a  talking-record  disk  driven 
at  seventy-eight  revolutions  per  minute,  the  usual  speed  for  Victor 
records,  a  loss  or  gain  of  a  thread  upon  the  record  makes  a  difference 
of  one-sixteenth  of  a  revolution  of  the  index  hands.  That  is  to  say, 
the  gear  between  the  revolving  record  and  the  index  hand  is  about 
sixteen-to-one. 

The  excess  speed  of  the  cinephone  film,  66  feet  per  minute  in- 
stead of  oO  feet  per  minute  for  standard  projection,  will  enable  the 
operator  to  turn  his  motion  head  for  cinephone  film  at  three-quarter 
speed  without  causing  an  objectionable  flicker  upon  the  picture 
screen,  thereby  enabling  the  talking  record  to  again  come  into 
perfect  accord  with  the  picture  film,  that  is,  enabling  the  index 
hand  of  the  talking  machine  to  catch  up  with  the  index  hand  of 
the  picture  screen. 

A  specimen  of  cinephone  film  is  shown  in  I^ig.  114,  showing  the 
index  dial  and  hand  photographed  into  the  lower  left-hand  comer 
of  each  of  the  images. 

COLORMOTOQRAPHY 

Color  photography  with  the  fixed  camera  has  been  an  accom- 
plished fact  for  several  years,  but  the  production  of  colored  motion 
pictures,  in  the  colors  of  nature,  by  photography  direct  from 
nature  with  color-sensitive  photographic  films,  has  only  lately 
reached  two  solutions,  one  of  which  is  called  the  Urban-Smith  proc- 
ess and  the  other  the  Friese-Green  process.  Both  of  these  have 
been  exhibited  publicly.  Other  processes  are  promised,  but  the 
promises  are  as  yet  unfulfilled. 


262 


MOTION  HEAD  1S7 

URBAN=SMITH   PROCESS 

The  motion  picture  itself,  the  black-and-white  kind,  utilizes  the 
persistence  of  vision  for  the  production  of  motion  in  the  picture, 
simulating  the  motion  of  the  subject  photographed.  The  Urban- 
Smith  process  utilizes  the  persistence  of  vision  still  further,  causing 
it  to  produce  also  color  in  the  picture  simulating  the  color  of  the 
subject  photographed.  Obviously,  it  would  be  possible  easily  to 
reproduce  in  blue  upon  the  picture  screen  a  picture  which  has  noth- 
ipg  but  blue  in  the  subject  photographed;  or  the  same  is  true  of  green 
if  the  subject  had  nothing  but  one  shade  of  green  in  it;  but  when  the 
subject  has  both  blue  and  green,  and  perhaps  red  and  yellow  as 
well,  how  shall  these  colors  be  preserved  separately  and  combined 
upon  the  screen  when  projected? 

The  Urban-Smith  answer  to  this  question  is  that  they  may  be 
photographed  separately  and  then  thrown  upon  the  screen  so  rapidly 
one  after  another  that  the  eye  of  the  spectator  (by  the  persistence  of 
vision)  sees  all  of  them  at  once.  This  fundamental  principle  of  record- 
ing and  reproducing  the  colors  of  nature  has  been  worked  out  in  a 
practical  form  for  motion-picture  theaters,  and  has  been  named 
"Kinemacolor."  The  working  colors  of  the  photograph  have  been 
reduced  to  two,  green  and  red  (or  orange).  The  film  when  examined 
before  projection  appears  quite  the  ordinary  black  and  white  film; 
the  color  is  given  to  the  light  rays  after  they  have  passed  through 
the  film.  The  pictures  are  projected  at  thirty-two  per  second,  or  120 
feet  of  film  per  minute,  a  speed  about  two  and  one-third  times  as 
fast  as  the  usual  projection  of  ordinary  motion  pictures. 

Making  Kinemacolor  Film  Pictures.  The  camera  is  provided 
with  a  double  shutter,  having  two  windows,  making  sixteen  revolu- 
tions per  second,  while  the  sensitive  film  is  shifted  thirty-two  times 
per  second.  This  corresponds  to  the  number  of  exposures,  since  the 
shutter  with  its  two  windows  makes  two  exposures  upon  the  film 
for  every  revolution  of  the  shutter. 

The  film  is  sensitive  to  light  of  all  colors,  and  the  shutter  carries 
in  each  of  its  windows  a  sheet  of  colored  gelatine,  one  window  being 
colored  green  and  the  other  window  being  colored  red  or  orange. 
Thus,  when  the  strip  of  sensitive  photographic  film  has  been  exposed 
in  such  a  camera,  and  subsequently  developed  into  a  negative,  it 


263 


188  THE  MOTION  PICTURE 

has  upon  it  one  picture  taken  through  a  green  window  with  green 
light  onlv,  and  the  next  picture  taken  through  a  red  window  with 
red  hght  only,  and  so  on  alternately  for  the  entire  length  of  the  film. 
In  addition,  a  spot  is  printed  opposite  each  green-light  picture  to 
identify  the  green-light  pictures  from  the  red-light  pictures,  for  all 
of  the  images  in  this  negative  film  are  merely  black-and-white,  with- 
out anv  traces  of  color  whatever. 

From  this  negative,  a  positive  print  is  made,  exactly  as  for  a 
black-and-white  picture.  The  guide  spots  for  the  green-Hght  pic- 
tures are  transferred  to  the  positive  print  and  serve  to  identify  the 
green-light  pictures  in  the  positive.  The  Kinemacolor  film  for  the 
projection  of  motion  pictures  in  natural  colors  now  is  complete  and 
readv  for  the  Kinemacolor  projecting  machine.  No  coloring  what- 
ever is  found  in  the  film.  Then  how  are  the  pictures  to  be  projected 
in  color? 

Production  of  Color.  It  is  generally  known  that  all  of  the  tints 
and  hues  of  nature  can  be  reproduced  by  a  correct  combination  of 
three  elementary  colors  in  proper  proportions.  Red,  yellow,  and 
blue  usually  are  used  as  a  set  of  elementary  or  primary  colors,  but 
orange,  green,  and  violet  serve  as  well. 

Printing  presses  turn  out  daily  numberless  pictures  in  colors, 
calendars  hang  upon  the  walls,  and  picture  postcards  travel  through 
the  mails  in  flocks,  bearing  the  colors  of  nature.  Yet  examine  them, 
and  the  largest  number  of  them  will  be  found  to  have  met  the  print- 
ing plate  but  three  times,  once  for  each  of  three  colors,  usually  red, 
yellow,  and  blue,  yet  each  shows  a  wide  variety  in  number  of  colors 
and  a  wide  variation  in  tones  of  each  color.  It  is  by  the  combination 
of  the  primary  colors  in  proper  proportions  that  these  effects  are 
attained,  and  the  same  principle  is  used  on  the  Urban-Smith  process 
of  color  motography. 

On  the  postcard,  the  colors  will  be  found  to  be  made  up  of 
numberless  small  spots  of  the  primary  colors,  intermingled,  so  that 
the  eye  sees  none  of  them  separately,  but  all  together,  the  colors 
being  mingled  in  the  eye.  The  Urban-Smith  process  also  throws 
from  the  screen  to  the  eye  the  different  primary  colors  in  different 
quantities  from  the  same  spots  on  the  screen,  and  the  colors  mingle 
in  the  eye  by  the  persistence  of  vision  to  produce  a  wide  variety  of 
shades  and  tintings. 


264 


MOTION  HEAD 


189 


^^^ 

^ 


Flag  in  Color.  There  is  presented  in  Fig.  115  a  reproduction 
of  a  Kinemacolor  photograph  of  the  British  flag,  a  flag  which  has  a 
bkie  field  crossed  by  red  stripes,  with  Hnes  of  white  bordering  the 
red  stripes  and  separating  the  red  and  bhie.  The  spot  for  identify- 
ing the  green-hght  picture  is  visible  in  the  margin  between  the  per- 
forations, opposite  the  second  and  fourth  pictures,  counting  from 
the  top  of  the  figure.  The  first  and  third  pictures,  counting  from 
the  top,  are  the  red-light  pictures. 

For  purposes  of  study,  consider  that  these  small  pictures  are 
cut  apart,  that  the  first  picture  is  placed  between  two  lantem-slide 
cover  glasses  of  clear  glass  and  projected 
upon  the  picture  screen,  and  that  the  sec- 
ond picture  is  placed  similarly  between  the 
two  other  cover  glasses  of  clear  glass  and 
projected  from  a  second  lantern  upon  the 
same  screen  and  upon  the  same  spot  of 
the  screen,  so  that  the  two  flags  from  the 
two  lanterns  will  be  focused  upon  each 
other  upon  the  picture  screen.  The  audi- 
ence will  see  but  one  flag,  not  realizing 
that  the  one  picture  is  projected  from  two 
lanterns. 

Note  that  the  second  lantern  has  the 
picture  with  the  green-light  spot,  therefore, 
it  has  the  green-light  picture,  so  slip  a 
sheet  of  green  gelatine  over  the  slide,  and 
at  the  same  time  slip  a  sheet  of  red  (or 
deep  red-orange)  gelatine  over  the  picture 
in  the  first  lantern.  This  produces  a  beam 
of  green  light  from  one  lantern  and  a  beam  of  red  light  from  the 
other  lantern,  but  when  they  fall  upon  the  picture  screen  on  the 
clear  space  all  around  the  flag  pictures  they  will  both  be  seen  by 
the  eye  at  once  and  the  combination  will  give  a  white  light,  or 
nearly  so;  hence  the  flag  will  be  seen  upon  a  white  background 
with  the  colored  beams  of  light,  just  as  it  was  before  the  colored 
gelatine  sheets  were  put  into  the  lanterns. 

The  same  is  true  of  the  lines  along  the  edges  of  the  stripes  or 
cross-bars  of  the  flag,  but  with  the  bars  themselves  it  is  different. 


Fig.  115. 


A  Kinemacolor 
Flag 


265 


190  THE  MOTION  PICTURE 

Note  that  the  top  image,  or  red-Ught  image,  is  clear  in  the  cross-hars, 
while  the  second  image  with  the  green-light  spot  is  dark  in  the  cross- 
bars. Then  the  red-light  lantern,  with  the  red  gelatine  color  screen 
and  the  red-light  image  of  the  flag,  will  project  red  light  upon  the 
cross-bar  portion  of  the  flag,  but  the  green-light  lantern,  with  the 
second  or  green-light  image,  which  is  opaque  in  the  bars,  will  be 
unable  to  project  any  green  light  upon  the  bars  of  the  flag  on  the 
screen  to  change  the  red  light  to  white,  hence  the  bars  of  the  flag  will 
be  seen  red  by  the  audience.  In  the  space  of  the  blue  field  of  tlie  flag, 
a  little  red  and  a  little  green  light  will  be  projected  through  the  half- 
tone of  the  picture  film,  combining  to  produce  the  blue  of  the  flag. 

Alternate  Projection.  In  the  Kinemacolor  projecting  machine, 
the  red-light  flag  and  the  green-light  flag  are  not  projected  at  the 
same  time,  as  was  considered  with  the  two  lanterns  for  purposes  of 
analysis  and  study,  but  they  are  projected  one  after  the  other  so 
rapidly  that  the  eye  retains  the  red  picture  while  the  green  picture 
is  being  projected,  and  then  in  turn  retains  the  green  picture  while 
the  next  red  picture  is  being  projected,  thus  actually  seeing  both 
pictures  at  once  by  the  principle  of  persistence  of  yision. 

The  beam  of  light  from  the  picture  film  is  colored  red  and 
green  alternately  by  a  shutter  upon  the  projecting  machine  similar 
to  that  in  the  camera  with  which  the  pictures  were  taken.  The 
shutter  has  t\\o  windows,  one  of  which  carries  a  piece  of  red  or  orange 
gelatine  and  the  otnei  of  which  carries  a  piece  of  gelatine  colored 
green.  The  green  gelatine  is  in  front  of  the  lens  while  the  green- 
light  image  is  being  projected  and  the  red  gelatine  is  in  front  of  the 
lens  while  the  red-light  image  is  being  projected.  In  this  manner, 
the  different  images  are  projected  with  the  color  of  light  which  made 
the  negatiye  in  the  camera,  and  the  light  giyen  to  each  portion  of 
the  screen  is  of  the  same  color  and  density  as  that  which  made  the 
corresponding  portion  of  the  negatiye,  which  is  to  say,  the  same  as 
that  which  was  giyen  to  the  lens  or  to  the  eye  of  the  observer  by  the 
actual  scene  motographed.  Because  of  the  speed  of  projection  and 
the  principle  of  the  persistence  of  yisioii,  the  red-light  pictures  and 
the  green-light  pictures  are  blended  together  in  all  portions  of  the 
picture  screen  at  once,  so  that  the  eye  sees  the  view  as  it  appeared 
before  the  camera,  with  all  its  colors  and  gradations  of  color  and  light 
and  shadow  in  all  its  dift'erent  parts. 


266 


o 


M  f-i 


MOTION  HEAD 


191 


Fig.  116  shows  a  reproduction  of  a  water  scene  motographed  in 
Kinemacolor  film. 

Kinemacolor  Machines.  The  Kinemacolor  film  is  made  to  be 
projected  at  a  speed  two  and  one-third  times  as  great  as  ordinary 
black-and-white  film.  No  ordinary  machine  will  stand  the  strain  of 
such  a  speed  of  projection,  and  a  special  Kinemacolor  projecting 
machine  has  been  built  for  the  work.  The  machine  should  be  run 
by  a  motor,  the  power  required  to  drive  it  at  its  high  speed  being 
almost  too  great  for  the  arm  of  the  operator,  although  a  short 
length  or  a  single  reel  of  Kinemacolor  may  be  turned  through  by 
hand.  A  reel  of  one  thousand  feet  of 
Kinemacolor  film  runs  but  eight  minutes 
on  the  picture  screen.  Let  any  operator 
try  to  turn  a  full  reel  through  an  ordinary 
projecting  machine  in  eight  minutes  and 
an  idea  will  be  had  of  the  power  and  speed 
required  of  the  Kinemacolor  projector. 

The  Kinemacolor  projector  is  fully 
adapted  for  the  projection  of  ordinary  black- 
and-white,  50-feet-per-minute  film,  merely 
by  removing  the  color  screen,  or  shutter 
having  the  colored  windows,  and  then  turn- 
ing the  machine  at  a  proper  rate  of  speed 
for  fourteen  images  per  second  instead  of 
thirty-two. 

All  of  its  parts  are  similar  to  the  gener- 
ally known  projecting  machines  of  America, 
except  the  intermittent  mechanism  for  the 
shift  of  the  film,  and  the  removable  color 
shutter.  The  machine  when  equipped  for  color  projection  carries 
two  shutters,  the  simple  shutter  for  black-and-white  pictures  being 
left  on  when  the  additional  color  shutter  for  Kinemacolor  pictures  is 
added.  A  view  of  the  operating  side  of  the  motion  head  is  shown 
in  Fig.  117  and  a  view  of  the  color  screen  or  color  shutter  is  shown  in 
Fig.  118. 

Intermittent  Mechanism.  The  intermittent  sprocket  of  the 
ordinary  type  of  projecting  machine  is  replaced  by  a  device  of  the 
beater  class,  shown  at  66  and  67  in  Fig.  117.    This  beater  cam  pulls 


Fig.   116.     A  Kinemacolor 
Water  Scene 


267 


192 


THE  MOTION  PICTURE 


slack  into  the  bottom  loop  of  the  film  at  every  revolution,  drawing 
the  fihn  down  through  the  film  gate  just  as  the  intermittent  sprocket 
does  in  the  usual  t^-pe  of  American  machine. 

In  threading,  the  film  is  carried  over  the  beater  dog  as  it  would 
be  carried  over  the  intermittent  sprocket,  except  that  there  are  no 
teeth  to  enmesh,  and  no  presser  roller  for  the  beater  dog.  The  course 
of  the  film  through  the  motion  head  is  seen  very  clearly  in  Fig.  117. 
The  upper  loop  between  the  upper  steady  feed  sprocket  and  the 

film  gate  should  be  rather  small 
when  the  beater  dog  has  just 
drawn  the  film  down. 

Adjusiment  of  Color  Screen. 
The  color  screen  is  made  of  thick 
sheets  of  gelatine  clamped  be- 
tween steel  frames,  as  shown  in 

I ^ -J      [      (fOF  ^   6/        frame  capable  of  being  removed 

from  the  shutter  shaft  which  car- 
ries it  upon  the  projecting  ma- 
chine, but  the  sheets  of  gelatine 
are  capable  of  being  removed 
from  the  frame. 

The  red  gelatine  is  used  in 
a  single  tliickness,  but  the  green 
gelatine  is  used  in  two  parts,  first 
a  single  thickness  covering  the 
whole  of  the  green  window,  then 
another  piece  of  green  covering 
the  middle  portion  and  giving  a 
thickness  in  the  middle  of  the  window.  The  object  is  to 
permit  an  adjustment  of  the  relative  volume  of  light  in  the  red- 
light  and  green-light  pictures,  or  in  the  red-light  and  green- 
light  beams  of  fight  throA\Ti  upon  the  screen  by  the  motion  head 
through  the  color  shutter  when  there  is  no  film  in  the  film  window. 
Wlien  the  color  shutter  is  adjusted  properly,  and  the  Kinemacolor 
motion  head  is  turned  rapidly  with  no  film  in  the  window,  the  picture 
screen  should  appear  white.  This  is  an  adjustment  that  the  Kinema- 
color operator  must  make. 


The  Kinemacolor  Motion  Head 


268 


MOTION  HEAD 


193 


The  color  of  the  red  gelatine  in  the  color  shutter  is  a  standard 
and,  therefore,  should  not  be  changed.  Were  the  color  shutter  put 
in  the  machine  with  only  a  single  thickness  of  green  gelatine,  the 
screen  would  be  greenish  white  when  the  motion  head  is  turned 
rapidly  without  a  picture  film  in  the  film  gate,  and  all  pictures 
when  projected  would  take  that  greenish  tint.  On  the  other  hand, 
were  two  thicknesses  of  the  full  size  of  green  gelatine  placed  in 
the  shutter,  the  screen  would  appear  a  light  orange. 

The  size  of  the  smaller  piece  of  green  gelatine  must  be  adjusted 
until  the  screen  appears  a  clear  white.  This  is  the  best  adjustment 
attainable,  and  when  done  has  adjusted  the  color  shutter  to  the  color 


Fig.  118.     The  Kinemacolor  Color  Shutter,  Showing  Red-Light  Window, 
Green-Light  Window,  and  Open  Spaces  for  Blue  Light 

of  the  arc  lamp.  The  adjustment  should  be  made  with  the  arc  of 
medium  length,  not  just  after  feeding,  nor  just  before  feeding  is 
needed.  Nor  should  the  color  of  the  screen  be  judged  just  after 
looking  at  the  arc,  for  the  arc  will  have  blinded  the  eye  and  will 
have  rendered  it  impossible  to  judge  the  color  of  the  screen. 

The  color  shutter  is  so  adjusted  upon  the  shaft  which  carries  it 
that  either  red  light  or  green  hght  will  be  admitted  to  the  picture 
screen  through  the  colored  gelatine  windows  when  the  lens  of  the 
motion  head  is  opened  by  the  opaque  shutter.  The  open  shts  of  the 
color  shutter  will  pass  the  lens  while  the  opaque  shutter  has  the 
lens  closed.     By  inspection  of  the  opaque  shutter,  it  will  be  seen 


939 


194  THE  MOTION  PICTURE 

that  the  shutter  is  not  black,  but  a  dark  blue,  thus  supplying  to  the 
picture  screen  a  third  tint  through  the  open  slots  of  the  color  shutter 
to  correct  some  of  the  tints  of  the  Kinemacolor  picture  when  pro- 
jected. 

Framing.  The  Kinemacolor  projecting  machine  has  a  larger 
range  in  framing  than  the  ordinary  machine,  since  it  is  necessary  to 
frame  to  either  one  of  a  pair  of  pictures  in  the  strip  of  film.  Thus 
an  image  may  be  accurately  centered  in  the  film  window  when  the 
film  is  at  rest  between  shifts  of  the  intermittent  movement,  and  when 
the  shutter  therefore  is  open,  but  if  the  image  be  the  red-light  image 
and  the  shutter  window  just  then  before  the  lens  be  the  green-light 
gelatine  window,  then  the  film  must  be  framed  forward  or  back  one 
whole  picture  image  to  bring  a  green-light  image  into  the  film  win- 
dow for  the  green  gelatine  of  the  color  shutter. 

Framing  Titles.  To  assist  in  the  proper  framing  of  the  pictures 
for  color  before  the  actual  pictures  begin  to  be  projected  upon  the 
screen,  the  titles  are  made  in  the  green-fight  images  only,  the  red- 
light  spaces  being  left  of  blank,  black  film  between  the  green-light 
title  images. 

The  title,  therefore,  must  be  framed  to  green  as  well  as  framed  to 
center  in  the  film  window  and  upon  the  picture  screen.  If  the  title 
comes  red-light  upon  the  screen,  frame  it  up  or  down  a  full  picture, 
making  it  green.  The  picture  which  follows  then  will  come  in  its 
proper  colors. 

Splicing.  Owing  to  the  hard  usage  of  the  film  because  of  its 
projection  at  such  a  high  rate  of  speed,  the  splices  must  be  strong. 
The  splices  should  be  a  half-picture  or  two  full  sprocket  holes,  in- 
stead of  a  quarter  picture  or  only  one  sprocket  hole,  as  is  the  case 
with  ordinary  film.  By  the  beater  type  of  shift  mechanism,  there  is 
no  intermittent  or  high-speed  sprocket.  All  of  the  sprockets  are 
steady  feed  and  reasonably  low  speed,  hence  able  to  negotiate  the 
less  flexible  splice  better  than  the  sprocket  shift. 

Splicing  for  Alternation.  This  is  splicing  for  color.  The  pic- 
tures in  the  unbroken  film  come  red-light,  green-light,  red-fight, 
green-light,  and  so  on,  and  this  order  must  be  preserved  when  cutting 
out  a  l)ad  spot  in  the  film  and  splicing  up.  Always  cut  an  even  num- 
\)CT  of  images.  Cut  out  one  and  a  half  and  lap  a  half,  thus  making 
a  cut  of  two  images,  or  four,  or  six,  as  may  be  necessary.    If  a  single 


270 


MOTION  HEAD  195 

red-light  image  were  cut  out,  it  would  leave  two  green-light  images 
together.  When  that  point  would  be  reached  in  the  projection  of 
the  film,  the  second  of  the  green-light  images  would  get  the  red-light 
window,  the  next  or  red-light  image  would  get  the  green-light  win- 
dow of  the  color  shutter,  and  so  on,  every  image  getting  the  wrong 
color  from  the  color  shutter.  Every  object  in  the  picture  upon  the 
screen  showing  any  color  at  all  would  change  its  color.  The  trees 
would  turn  red  instead  of  green,  the  sky  orange  instead  of  blue.  The 
picture  upon  the  screen  would  be  spoiled  until  the  projection  operator 
could  notice  the  condition  and  frame  the  film  backward  or  forward 
one  whole  image. 

When  it  is  found  that  a  film  changes  thus  in  projection,  a  splice 
improperly  made  will  be  found  at  the  point  where  the  change  occurs. 
This  should  be  cut  and  respliced,  taking  out  only  one  image,  to  change 
the  film  back  to  the  proper  alternation  of  red-light,  green-light,  and 
so  on. 

The  green-light  spot  opposite  the  green-light  images,  shown 
in  Figs.  115  and  116,  will  aid  in  making  the  splices  correct  for  color, 
and  will  aid  in  inspecting  any  splices  which  may  be  found  in  a  film 
not  yet  projected.  In  some  Kinemacolor  films,  the  green-light  spot 
is  not  printed  photographically,  but  is  made  by  a  spot  of  green  dye 
or  pigment  upon  the  gelatine  of  the  film,  or  by  a  short  green  line  upon 
the  margin  opposite  the  green-light  picture. 

In  the  absence  of  either  photographic  spot  or  green  mark,  the 
alternation  of  pictures  still  may  be  observed  in  most  Kinemacolor 
films  by  the  comparative  density  of  the  images,  or  of  some  particular 
portion  of  the  images.  If  there  are  green  trees,  they  will  be  light 
and  dark  in  alternate  pictures,  being  lighter  in  the  green  pictures. 
The  sky  if  blue  will  be  lighter  in  the  green  pictures,  but  if  gray  or 
cloudy  it  will  be'of  about  the  same  density  in  both.  Perhaps  a  dress  or 
house  may  give  the  light-dark-hght-dark  alternation,  and  in  sphcing 
it  matters  not  which  is  light  and  which  is  dark,  so  long  as  the  alter- 
nation of  light-dark-light-dark  for  the  series  of  pictures  is  continued 
properly  over  the  splice. 

In  Fig.  115,  the  bars  of  the  flag  give  the  light-dark  alternation, 
being  light  in  the  red-light  picture,  while  in  Fig.  116  the  sky  gives 
the  light-dark  alternation,  being  light  in  the  green-light  picture. 

Film   Inspection.     A   Kinemacolor   film   should   be   inspected 


271 


196  THE  MOTION  PICTURE 

thoroughly  by  the  careful  operator,  who  is  jealous  of  his  results  and 
of  his  reputation,  before  projecting  it  for  an  audience.  Every  splice 
should  be  looked  at,  first,  to  see  that  it  is  not  out  of  frame  in  the 
ordinary  manner  by  a  fraction  of  a  picture,  and,  second,  to  see  that 
it  is  not  out  of  frame  for  color  by  the  connection  of  two  light  images 
or  two  dark  images,  instead  of  having  a  light  and  a  dark  image  meet 
at  the  splice.  Also,  note  where  the  title  joins  the  picture  which 
follows  it,  and  study  it  to  determine  whether  the  second  image, 
or  second  image-length  of  film,  after  the  last  title  image,  is  a  green- 
lio-ht  image  as  it  should  be.  Also  look  carefully  for  any  broken  sprocket 
holes  or  weak  places  in  the  film  which  might  break  during  the  run, 
bearing  in  mind  that  the  Kinemacolor  film  gets  a  harder  bumping 
and  jerking  than  any  simple  black-and-white  film,  and  that  a  weak 
place  is  Hkely  to  break  in  the  run.  Any  of  these  troubles  found  should 
be  corrected.  Then  every  projection  of  the  film  should  be  watched 
for  indications  of  a  weakening  film.  The  film  is  being  subjected  to 
harder  ser\ace,  and  a  more  rigorous  care,  if  possible,  is  necessary 
than  with  black-and-white  working  at  only  50  feet  per  minute. 

Oiling.  The  high-speed  parts  of  the  Kinemacolor  projector 
should  be  oiled  only  with  a  good  grade  of  sewing  machine  oil,  and 
they  should  be  oiled  for  every  reel  of  film,  that  is,  for  continuous 
Kinemacolor  projection,  the  rapidly  moving  parts  of  the  motion 
head  should  be  oiled  every  eight  minutes.  The  high  speed  requires 
a  thin  oil,  and  a  thin  oil  works  out  of  the  journals  quickly  and  requires 
renewal. 

For  the  journals  which  have  the  less  rapid  motion,  a  medium 
heavy  machine  oil  may  be  used,  such  as  is  used  for  ordinary  pro- 
jection machines,  oiling  up  at  the  beginning  of  the  afternoon  and 
again  at  the  beginning  of  the  evening  run,  or  more  frequently  if  the 
use  of  the  machine  is  practically  continuous. 

The  upper  reel  or  feed  reel  requires  special  attention,  because 
as  the  film  nears  its  end  the  speed  of  revolution  of  that  reel  becomes 
pretty  high.  The  fixed  spindle  of  the  feed  magazine,  over  which  the 
feed  reel  slips,  should  be  lubricated  with  vaseline,  and  care  should 
be  taken  to  see  that  the  reel  turns  freely  on  the  spindle  when  the 
magazine  door  is  closed. 

Arc  Lamp.  With  one  window  of  the  color  shutter  taking  out 
all  the  green  light  and  passing  only  the  red  light  for  the  red-light 


272 


MOTION  HEAD  197 

images,  and  with  the  other  window  of  the  color  shutter  taking  out 
all  the  red  hght  and  passing  only  the  green  light  for  the  green-hght 
images,  it  will  be  seen  that  a  total  of  only  half  the  light  of  the  arc 
which  passes  through  the  film  and  the  lens  ev^er  reaches  the  picture 
screen,  the  other  half  (sometimes  the  green  half,  sometimes  the  red 
half)  never  getting  any  farther  than  the  color  shutter. 

To  give  an  equal  brightness  upon  the  picture  screen,  compared 
with  black-and-white  pictures,  the  Kinemacolor  film  and  color 
shutter  require  a  much  brighter  arc.  The  resistance  of  the  rheostat 
may  be  reduced,  or  two  rheostats  may  be  connected  in  multiple  to 
give  the  additional  current,  together  with  carbons  of  a  slightly  larger 
diameter,  say  |-inch. 

Lamp  currents  of  60,  75,  and  even  100  amperes  have  been  sug- 
gested. The  maximum  current  used  must  always  be  a  compromise 
between  screen  brilliancy  and  condenser  breakage. 

Direction  of  Film  Wind.  The  feed  reel  requires  the  film  to  be 
wound  with  the  emulsion  side  "inside"  when  the  reel  is  full,  that  is, 
the  film  is  started  with  the  emulsion  side  next  the  core  when  rewind- 
ing. The  take-up  reel  turns  "counterclockwise"  and  winds  the  film 
up  with  the  emulsion  side  "outside,"  the  film  being  started  upon 
the  take-up  with  the  celluloid  side  next  the  core.  \\Tiile  the  feed 
reel  might  run  in  either  direction,  it  is  designed  to  nm  clockwise 
when  feeding. 

FRIESE=QREEN  PROCESS 

It  may  be  said  of  the  Friese-Green  process  of  motion  pictures 
in  natural  colors  by  colorphotography  direct  from  nature  that  it  is 
being  developed  in  England.  How  nearly  ready  for  the  market  the 
Friese-Green  process  is,  cannot  be  said.  Several  very  successful 
pubhc  exhibitions  of  the  color  projection  achieved  by  the  process 
have  been  given. 

The  Friese-Green  process  resembles  the  Urban-Smith  process 
in  that  it  produces  the  innumerable  variations  of  color  in  nature  by 
recording  them  in  a  few  primary  colors  and  then  recombining  them 
upon  the  picture  screen  by  persistence  of  vision.  The  Friese-Green 
system  of  projection  uses  two  projecting  lenses,  projecting  two  images 
of  two  colors  upon  the  picture  screen  at  the  same  time,  shifting  each 
one  fourteen  times  per  second,  that  is,  at  the  regular  speed  of  shift- 


273 


198 


THE  MOTION  PICTURE 


ino-  ordinary  black-and-white  picture  film.  The  negative  is  made 
through  a  color  shutter  of  three  colors.  The  colors  really  are  orange, 
green,  and  violet,  but  are  called  red,  green,  and  blue. 

Process  of  Manufacture^  The  process  of  making  is  by  the  use  of 
a  double  camera,  as  shown  in  Fig.  119,  the  camera  being  composed 
of  two  motographic  mechanisms  built  into  a  single  case,  each  mechan- 


Fig.  119.     The  Friese-Green  Color-Motography  Camera  in  Operation 

ism  using  its  own  roll  of  sensitive  film  and  its  own'  intermittent  shift 
mechanism,  and  having  its  own  lens  and  its  owti  color  shutter.  They 
are  linked  by  being  driven  by  the  same  crank  shaft,  and  further  by 
having  one  opaque  shutter  common  to  the  two  lenses.  One  of  the 
lenses  closes  while  the  other  opens,  alternating  until  the  picture  is 
completed  upon  both  reels  of  negative  film,  the  alternate  pictures  being 
upon  the  two  reels,  respectively,  when  finished.  In  Fig.  119,  the  right 
hand  of  the  operator  turns  the  crank  which  drives  the  film  mechanism, 
while  the  left  hand  is  upon  the  panoram  handle  of  the  tripod  head. 


274 


MOTION  HEAD  199 

In  addition  to  alternation  in  taking  the  negative  images  of  the 
subject  photographed,  the  two  lenses  take  the  image  in  a  different 
color  of  light  at  each  exposure.  The  color  shutter,  or  color  filter, 
changes  for  each  exposure  in  each  camera  in  the  order  of  blue,  green, 
red,  blue,  green,  red,  and  so  on,  and  as  the  two  series  of  pictures  are 
taken  in  alternation  they  are  taken  as  follows: 

(1)  A  green-light  image  with  the  left  camera;  (2)  a  blue-light 
image  with  the  right  camera;  (5)  a  red-light  image  with  the  left 
camera;  (4)  a  green-light  image  with  the  right  camera;  (S)  a  blue- 
light  image  with  the  left  camera;  (6)  a  red-Hght  image  with  the  right 
camera;  (7)  a  green-light  image  with  the  left  camera;  and  so  on. 

Projection  of  Film.  In  projecting,  a  similar  color  shutter  of 
three  colors  is  employed.  A  double  motion  head  is  used,  with  two 
arc  lamps,  two  intermittent  mechanisms,  and  two  lenses,  also  two 
color  shutters.  The  intermittent  mechanisms  and  shutters  are  driven 
by  the  same  crank  handle,  as  are  also  the  two  color  shutters. 

A  combination  of  simultaneous  and  alternative  color  projection 
is  achieved  by  the  two  lenses  and  mechanisms  of  the  Friese-Green 
projection  head,  as  follows: 

(1)  The  left  lens  projects  a  green-light  image,  and  while  the 
green  light  of  the  left  lens  is  still  upon  the  picture  screen  (3)  the 
right  lens  projects  a  blue-light  image  upon  it,  thus  giving  the  two 
colored  images  green  and  blue  upon  the  picture  screen  at  the  same 
time;  but  the  left  lens  now  cuts  off  the  green-light  image  and  shifts 
its  film  and  its  color  shutter,  and  (5)  projects  a  red-light  image  upon 
the  picture  screen  while  the  blue-light  image  of  the  right  lens  is  still 
upon  it,  thus  giving  two  images,  blue  and  red,  upon  the  picture 
screen  at  the  same  time;  now  the  right  lens  cuts  off  the  blue-light 
image  and  shifts  its  film  and  color  shutter,  and  (4)  projects  a  green- 
light  image  upon  the  screen  while  the  red-light  image  of  the  left  lens 
still  continues,  thus  giving  two  images,  red  and  green,  upon  the  pic- 
ture screen  at  the  same  time;  again,  while  the  green-light  image  from 
the  right  lens  continues,  the  left  lens  shifts  and  (5)  projects  a  blue- 
light  image,  thus  giving  two  images,  green  and  blue,  upon  the 
picture  screen  at  the  same  time.  This  cycle  of  colors  is  repeated 
indefinitely  or  until  the  end  of  the  scene.  As  the  images  are  shifted 
for  color,  each  image  shows  a  progressive  position  of  all  of  the  objects 
in  motion  in  the  subject,  so  that  motion  as  well  as  color  is  depicted. 


275 


200  THE  MOTION  PICTURE 

The  Friese-Green  picture  films  when  on  reels  of  course  come 
in  pairs,  and  a  pair  of  reels  of  1,000  feet  each  will  run  upon  the  screen 
twenty  minutes,  each  film  running  50  feet  per  minute. 

Splices.  Splices,  if  made  at  all,  require  great  skill  and  care. 
A  break  may  be  repaired  sometimes  by  a  patch  without  cutting  out 
any  of  the  film,  but  if  any  cut  is  to  be  made,  it  is  necessary  to  cut 
three  images  from  each  of  the  two  films,  and  in  the  same  place,  that 
unison  between  the  two  films  of  the  pair  may  be  maintained,  and 
that  synchronism  between  the  images  and  the  color  shutters  may 
be  maintained. 

Color  Shutter.  The  color  shutter  of  the  Friese-Green  camera 
and  projecting  machine  is  not  the  disk  of  the  Urban-Smith  device, 
but  a  transparent  film  band,  endless,  colored  in  sections  with  the  three 
colors,  and  traveling  with  the  film  through  the  film  gate  of  camera 
or  projecting  machine,  respectively. 

Care  in  threading  up  is  necessary,  with  reference  to  the  film 
pair,  to  get  correspondence,  and  with  reference  to  framing  for 
color  of  the  two  color  shutters  or  color  bands. 

Development  of  S}'Stem.  To  show  as  far  as  possible  the  progress 
which  has  been  made  in  the  development  of  the  Friese-Green  system, 
and  the  time  which  has  been  consumed  in  the  experiments,  the  fol- 
lowing is  quoted  from  an  English  magazine.  The  Kinemaiograph 
Weekly,  of  November  24,  1910: 

At  Pendleton's  Pictures,  Co-operative  Hall,  Crewe,  on  Thursday  last, 
Mr.  Friese-Green  gave  a  display  of  his  system  of  natural  color  animated 
photography. 

The  pictures  were  shown  during  the  ordinary  program,  an  announce- 
ment being  made  from  the  platform  that  a  picture  in  color  of  Mr.  Friese- 
Green 's  son  signaling  with  colored  flags,  taken  six  years  ago,  and  one  as 
recently  as  two  months  ago,  would  be  sho^VTi.  These  films,  it  was  explained, 
were  taken  in  the  laborator}^  and  the  commercial  results  of  Mr.  Friese- 
Green's  labors  would  be  submitted  in  about  a  month's  time. 

In  the  six-year-old  picture,  three  colors  apparently  were  employed  and 
the  machine  ran  at  ordinary  speed.  The  results  were  crude,  the  picture  was 
unsteady  and  fuzzy,  and  occasionally  such  colors  as  there  were  would  dis- 
appear altogether. 

The  two-year-old  results  were  very  much  better.  The  subject  was  a 
revolving  vase  of  flowers,  but  it  was  revolved  so  slowly  as  to  be  almost  a  still 
picture.  There  was  a  lack  of  true  color  in  the  blooms,  but  now  and  then  a 
fine  stereoscopic  effect  appeared. 

The  last,  and  two-months-old  picture  was  again  an  improvement,  and 


276 


MOTION  HEAD  201 

represented  a  colored-ware  dessert  dish  containing  fruits.  The  results  obtained 
were  curiously  varied.  Intermittently  the  color  rendering  would  appear  to 
be  very  good  indeed,  and  the  stereoscopic  effects  produced  by  the  dish  revolv- 
ing would  be  very  pronounced,  giving  a  beautiful,  soft,  and  natural  appear- 
ance. The  unsteadiness,  however,  was  very  great,  and  the  defects,  it  must 
be  confessed,  were  largely  apparent. 

It  remains  to  be  seen  what  Mr.  Friese-Green  can  accomplish  when  he 
comes  to  do  outdoor  work;  the  films  described  above  were  the  results,  of  course, 
of  long  exposures  and  slow  rates  of  speed.  Whether  his  methods  infringe  any 
of  the  master  patents  is  a  matter  upon  which  we  do  not  feel  called  upon  to 
express  an  opinion.  That  question  may  be  left  with  those  directly  interested. 
It  is  apparent  from  the  above  account  of  the  results  obtained  that  progress 
has  been  made,  and  we  wish  Mr.  Friese-Green  success  in  his  continued  efforts. 

FILM  MANUFACTURERS 

The  object  of  this  Hst  is  to  give  to  the  reader  some  Httle  knowl- 
edge of  any  manufacturer  whose  name  or  trademark  he  may  see 
upon  a  film.  The  list  does  not  pretend  to  be  complete,  not  even  for 
the  manufacturers  in  the  United  States.  In  many  instances,  no  in- 
formation other  than  the  home  office  address,  or  the  American  im- 
porter's name  and  address,  is  given.  Possibly  some  of  the  manufac- 
turers mentioned  have  discontinued  the  production  of  films,  but  so 
long  as  their  films  still  are  used  in  picture  theaters,  such  data  as  is 
given  concerning  them  will  have  an  interest  for  that  reason. 

Adolpho  Croce,  Milan,  Italy. 

Ajax  Film  Company,  A.  J.  Clapham,  Managing  Director,  12  East  15th 
Street,  New  York,  N.  Y. 

"Ambrosio."  Societa  Anonima  Ambrosio,  Torino,  Italy.  Films  im- 
ported into  United  States  by  New  York  Motion  Picture  Company,  1  Union 
Square,  New  York,  N.  Y.,  and  sold  through  the  Motion  Picture  Distributing 
&  Sales  Co. 

Ambrosio  Film  Manufacturing  Company,  16  Rue  St.  Marc,  Paris, 
France.  Films  imported  into  United  States  by  New  York  Motion  Picture 
Company,  1  Union  Square,  New  York,  N.  Y. 

American  Cinephone  Company,  124  East  25th  Street,  New  York,  N.  Y. 
Controlling  patents  for  the  Cinephone,  a  talking  picture  device,  for  the  United 
States.    Markets  its  product  only  through  the  American  Kinograph  Company. 

American  Film  Manufacturing  Company,  A.  M.  Kennedy,  General 
Manager,  Bank  Floor,  Ashland  Block,  Chicago,  111.  Making  picture  film 
under  the  sign  of  the  "Flying  A."  Sales  through  the  M.  P.  Distributing  & 
Sales   Co. 

American  Kinograph  Company,  124  East  25th  Street,  New  York,  N.  Y., 
J.  A.  Toupin,  Manager.  Operating  under  the  Cinephone  patents.  Supplies 
Cinephone  sound  records  and  picture  film  for  the  Cinephone  Talking  Pictures, 
also  Cinephone  talking  machines  for  the  Cinephone  sound  records. 


277 


202  THE  MOTION  PICTURE 

American  Motor  Racing  Picture  Company,  330  East  3oth  Street, 
Chicago,  Illinois.     Irregular  releases  of  special  film  pictures. 

American  Mutoscope  and  Biograph  Company,  New  York,  N.  Y. 
Commonly  called  the  "Biograph  Company."  Trademark,  an  "AB"  mono- 
gram in  a  circle  Offices  and  studio  in  New  York.  Office  address,  11  East 
14th  Street,  New  York,  N.  Y.  Studio  also  in  southern  California  Licensed 
imder  patents  controlled  by  the  Motion  Picture  Patents  Company  of  America 
Film  leased  to  licensed  film  exchanges  only. 

Animated  Motion  Picture  Patents  Company,  New  York,  N.  Y.  A 
patent-holding  company  controlling  a  patent  issued  to  Meredith  Jones  for  a 
camera  making  a  motion  picture  without  stopping  the  film  behind  the  lens. 

Animatophone  Syndicate,  Ltd.,  11  Denman  Street,  Piccadilly  Circus, 
London,  W.,  England.       Talking  and  Singing  Pictures. 

Aquila  Film  Manufacturing  Co.,  Torino,  Italy. 

Atlas  Film  Company,  10  East  15th  Street,  New  York,  N.  Y.  Films  sold 
through  the  Distributing  and  Sales  Company.  Manufacturing  picture  films 
imder  the  trademark  of  Atlas  supporting  the  globe  of  the  earth  with  a  picture 
film  encircling  both  athlete  and  globe. 

Barker  Motion  Photography,  Ltd.,  Topical  House,  1  Soho  Square, 
London,  W.     Sign  of  the  Bulldog. 

Bat  Films.     Lyons,  France,  8  Rue  du  President  Carnot. 

Bavaria   Film    Manufacturing   Company,    Strassbourg. 

"Biogr.\ph"  Film,  the  American  Mutoscope  &  Biograph  Co. 

"Bison"  trademark,  New  York  Motion  Picture  Manufacturing  Co. 

W.  Butcher  &  Sons,  Ltd.,  Camera  House,  Farringdon  Avenue,  London 
E.  C,  England.    Making  picture  films  under  the  trademark,  "Empire." 

Capitol  Film  Co.,  Washington,  D.  C,  Sig.  G.  Bernstein,  General  Man- 
ager. Making  picture  films  under  the  name  of  "Capitol  Films,"  with  the 
sign  of  the  capitol  dome  in  the  letter  "C." 

Carlton  Motion  Picture  Laboratories,  1  Union  Square,  New  York, 
N.  Y.  Films  sold  only  through  the  M.  P.  Distributing  &  Sales  Co.  Making 
picture  films  under  the  trademark  "Reliance." 

Champion  Film  Company,  Mark  M.  Dintenfass,  General  Manager,  12 
East  15th  Street,  New  York,  N.  Y.  Making  picture  film  under  the  trademark 
"Champ"  and  the  sign  of  the  victorious  gladiator.  Sells  through  the  ^I.  P. 
Distributing  &  Sales  Co. 

"Chicken  Film,"  Pathe  Freres,  sometimes  so  called  because  of  the 
trademark,  the  sign  of  the  red  rooster. 

E.  G.  Clement,  30  Rue  du  Petites-Ecuries,  Paris,  France. 

Columbia  Film  Company,  301  West  27th  Street,  New  York,  N.  Y.  Sells 
only  through  the  M.  P.  Distributing  &  Sales  Co. 

Continental  Film  Manufacturing  Company,  Copenhagen. 

Cosmopolitan  Film  Company,  Ltd.,  London,  England. 

Cricks  &  Martin,  London,  England.  Makers  of  film  pictures  under 
the  "Lion's  Head"  trademark. 

Defender  Films,  Wm.  H.  Swanson,  General  Manager,  111  East  14th 
Street,  New  York.    Sold  only  through  the  M.  P.  Distributing  &  Sales  Co. 

Ste.  Drankoff,  12  Nicolaeiwich,  Saint  Petersburg,  Russia. 

Eclair  Films,  Paris,  France,  8  Rue  St.  Augustin. 


fl 


278 


MOTIOxN  HEAD  203 

Edison  Manufacturing  Company,  65  Lakeside  Avenue,  Orange,  New 
Jersey.  Making  picture  films  with  the  trademark  of  the  "Circle  E."  Licensed 
by  the  Motion  Picture  Patents  Company  of  America,  which  controls  the  Edison 
patents.    Films  are  leased  to  licensed  film  exchanges  only. 

Essanay  Film  M.\nufacturing  Company,  435  North  Clark  Street, 
Chicago,  111.  Studios  in  Chicago  and  Colorado.  Licensed  under  the  patents 
controlled  by  the  Motion  Picture  Patents  Company  of  America.  Leases  film 
to  licensed  fUm  exchanges  only.     Trademark,  the  Indian  head. 

Film  d'Art  Film  Manufacturing  Company,  Paris,  France. 
The  Gaumont    Company,    Paris,   France.       Office,   57  Rue   St.   Roch. 
Usines  et  Theater,  12  Rue  de  Alouettes,  Paris.     American  office,   125  East 
23rd  Street,    New   York.      Films   imported    into   United   States   by   George 
Kleine,  Chicago,  111. 

Gnome  Motion  Picture  Company,  offices  and  studios  at  southwest 
corner  of  Park  and  Tremont  Avenues,  Bronx,  New  York,  N.  Y.  Licensed 
under  patents  of  the  Animated  Picture  Patents  Company. 

Great  Northern  Film  Company.  Home  office,  "Nordisk  Film  Company, 
Copenhagen."  American  office,  7  East  14th  Street,  New  York,  N.Y.  Trade- 
mark of  the  Polar  Bear  on  the  Earth  Globe. 

Hepworth  Manufacturing  Company,  London,  England,  making 
picture  films  under  the  trademarks  of  "Hepworth"  and  "Hepwix." 

HisPANO  Films,  Barcelona,  Spain,  Craywinckel,  20  San  Gervasio. 
David  Horsley,  German  Savings  Bank  Building,  4th  Avenue  and  14th 
Street,  New  York,  N.Y.    Making  picture  films  under  the  trademark  of  "Nestor." 
Sold  through  the  M.  P.  Distributing  &  Sales  Co. 

"Imp"  trademark,  Independent  Motion  Picture  Co. 
Independent  Moving  Picture  Company  op  America,  102  West  101st 
Street,  New  York,  N.  Y.  Carl  Laemmle,  President.  Manufacturing  picture 
films  under  the  trade  name  "IMP"  and  the  trademark  of  an  imp  associated 
with  a  shield  design  bearing  the  letters  "IMP."  Films  sold  through  the 
Motion  Picture  Distributing  and  Sales  Company. 

Itala  Film  Manufacturing  Company,  Torino,  Italy.  Films  imported 
into  United  States  by  New  York  Motion  Picture  Company,  1  Union  Square, 
New  York,  N.  Y. 

Kalem  Film  Manufacturing  Co.,  New  York,  N.  Y.  Making  picture 
films  under  the  name  "Kalem"  and  the  sign  of  the  blazing  sun  with  the  word 
"Kalem."  Licensed  by  the  Motion  Picture  Patents  Company  of  America. 
Films  leased  to  licensed  film  exchanges  only. 

KiNEMACOLOR  COMPANY  OF  America,  Allcntown,  Pa.  Making  Kinema- 
color  picture  films  and  manufacturing  Kinemacolor  projecting  machine. 
Kinemacolor  is  a  process  of  motion  pictures  in  natural  colors  by  color  pho- 
tography direct  from  nature. 

"KiNETo"  Films.  Kineto,  Ltd.,  48  Rupert  Street,  Shaftsbury  Avenue, 
London,  W.,  England. 

George   Kleine,  52   State   Street,  Chicago,  111.     Imports  "Gaumont" 

and  "Urban-Eclipse"  films  into  America  under  license  of  the  Motion  Picture 

Patents  Company  of  America.     Films  are  leased  to  licensed  exchanges  only. 

"Latium"  Film,  Manifattura  Cinematografica  Italiana. 

"Le    Lion"    Cinematographes    Company,    15    Rue    Grange-Bateliere, 


279 


204  THE  MOTION  PICTURE 

Paris,  France.  Manufacturing  films  under  the  trademark  of  the  lion  ram- 
pant mauling  a  roll  of  film. 

"Lion's  Head"  Film,  Cricks  &  Martin,  London,  England. 

LuBiN  Manufacturing  Company,  Philadelphia,  Pa.  Making  picture 
film  under  the  trademark  of  the  Liberty  Bell.  Licensed  under  the  patents 
controlled  by  the  Motion  Picture  Patents  Company  of  America.  Leases  film 
to  licensed  film  exchanges  only. 

Lux  Film  Manufacturing  Company,  Rue  Louis-le-Grand,  Paris, 
France. 

Manif.\ttur.4.  Cinematografica  It.\lia,  77  Via  Appia  Nouva,  Rome, 
Italy.    Making  picture  films  under  the  trademark,  "Latium  Film." 

G.  Melies,  New  York,  N.  Y.  Making  picture  films  under  the  trade- 
mark of  the  "Star."  Licensed  by  the  Motion  Picture  Patents  Company  of 
America.     Films  leased  to  licensed  film  exchanges  only. 

Motion  Picture  Distributing  and  Sales  Company,  111  East  14th 
Street,  New  York,  N.  Y.  Act  as  selling  agents  for  a  number  of  American 
and  Foreign  manufacturers.  Handle  Eclair,  Imp,  Yankee,  Bison,  Powers, 
Thanhouser,  Ambrosio,  Atlas,  Champion,  Nestor,  Itala,  Defender,  Lux, 
Cines,  Solax,  Great  Northern,  Columbia,  Capitol  and  Reliance  films  for  the 
United  States. 

Motion  Picture  Patents  Company  of  America,  10  Fifth  Avenue,  New 
York,  N.  Y.  A  company  organized  to  control  the  Edison,  Biograph,  Armat, 
and  Vitagraph  patents  pertaining  to  the  motion  picture  industry.  Some  of 
these  patents  are  the  following:  Reissue  12,192;  578,185;  580,749;  586,953; 
588,916;  673,329;  673,992;  707,934;  722,382;  744,251;  770,937;  771,280; 
785,205  and  785,237.  The  following  companies  are  licensed  by  the  M.  P. 
Patents  Company  to  manufacture  picture  film  vmder  the  above  listed  patents: 
The  American  Mutoscope  and  Biograph  Company  of  New  York  City;  the 
Edison  Manufacturing  Company  of  Orange,  New  Jersey;  the  Essanay  Com- 
pany of  Chicago;  the  Kaleni  Company  of  New  York  City;  Lubin  Manufacturing 
Company  of  Philadelphia;  Pathe  Frhres  of  Bound  Brook,  New  Jersey;  the  Selig 
Polyscope  Company  of  Chicago;  the  Vitagraph  Company  of  America  of  New 
York  City;  and  G.  Melies  of  New  York  City.  In  addition,  Pathe  Fr^res  are 
licensed  to  import  from  their  factories  in  France,  and  George  Kleine  of  Chicago 
is  licensed  to  import  "Gaumont"  and  "Urban-Eclipse"  films.  This  makes  a 
total  of  ten  licensees  of  the  Motion  Picture  Patents  Company.  The  output  of 
each  of  the  licensees  is  limited  by  the  terms  of  its  license.  All  films  manu- 
factured or  imported  under  the  licenses  of  the  IMotion  Picture  Patents  Company 
are  not  sold,  but  remain  the  property  of  the  manufacturer  or  importer,  being 
leased  to  licensed  film  exchanges  only  for  a  term  of  months,  during  which  time 
the  licensed  film  exchange  rents  the  films  to  exhibitors,  and  at  the  end  of  which 
time  the  exchange  returns  the  film  to  the  manufacturer  or  importer  to  be 
destroyed.  By  this  means,  only  the  latest  films  may  be  obtained  from  the 
licensed  film  exchanges.  The  object  is  to  cause  the  withdrawal  from  theater 
exhibition  of  films  which  have  had  a  reasonable  amount  of  wear,  and  to  main- 
tain as  high  a  standard  as  possible  in  the  film  theaters  both  for  lateness  of 
titles  and  freedom  from  wear  of  the  films. 

National  Film  Manufacturing  &  Leasing  Co.,  12  East  Fifteenth 
Street,   New   York  City.     A  manufacturing  and  leasing  company  operating 


280 


MOTION  HEAD  205 

independently  of  the  Motion  Picture  Patents  Company  of  America,  and 
independently  of   the  Motion  Picture  Distributing  and  Sales  Company. 

Navone  Film,  Torino,  Italy. 

"Nestor"  Films,  made  by  David  Horsley,  German  Savings  Bank  Build- 
ing, 4th  Avenue  and  14th  Street,  New  York,  N.  Y. 

New  York  Motion  Picture  Company.  Offices  and  Studio  in  New 
York  City.  Office  address,  Lincoln  Building,  1  Union  Square,  New  York, 
N.  Y.  Making  picture  film  under  the  trademark  of  "Bison"  and  the  sign  of 
a  buffalo  rampant.  Sells  film  only  through  the  M.  P.  Distributing  &  Sales  Co. 
Importing  agents  for  the  United  States  for  "Ambrosio"  and  "Itala"  films. 

Paragon  Bioscope  Company,  Ltd.,  13  Cecil  Court,  Charing  Cross  Road, 
London,  W.  C. 

Pathe  Freres.  Trademark  of  the  Red  Rooster.  Home  office,  14  Rue 
Favart,  Paris,  France.  American  offices  in  New  York,  Chicago  and  San 
Francisco.  Two  studios  in  France  and  an  American  studio  and  factory  at 
Bound  Brook,  New  Jersey.  Produce  American  and  foreign  subjects,  import- 
ing many  foreign  subjects  into  America.  Leaders  in  so-called  "hand  colored" 
pictures,  colored  by  stains  in  an  imitation  of  the  colors  of  nature,  the  colors 
being  applied  to  the  film  by  machinery.  American  factory  and  American 
importations  of  foreign  films  licensed  under  patents  controlled  by  the  Motion 
Picture  Patents  Company  of  America.  Films  leased  to  licensed  film  exchanges 
only. 

The  Powers  Company,  241st  Street  and  Richardson  Avenue,  New  York, 
N.  Y.  Making  picture  films  under  the  trademark  of  "Powers  Picture  Plays." 
Sales  through  the  M.  P.  Distributing  &  Sales  Co.  This  company  takes  its 
name  from  "Pat  Powers,"  and  should  not  be  confused  with  the  Nicholas 
Power  Company,  which  makes  the  Cameragraph  projecting  machines  and  does 
not  make  film. 

"Reliance"  trademark,  Carlton  Motion  Picture  Laboratories. 

Revier  Motion  Picture  Company,  H.  Revier,  President,  Majestic 
Theater  Building,  Salt  Lake  City,  Utah.  The  trademark  is  a  picture  of  a 
temple   with   the  word    "Revier." 

Selig  Polyscope  Company,  Chicago,  Illinois.  Offices  at  Dearborn  and 
Randolph  Streets.  Studio  and  factory  at  North  Western  Avenue  and  Irving 
Park  Boulevard.  Making  picture  film  under  the  sign  of  the  "Diamond  S." 
Licensed  by  the  Motion  Picture  Patents  Company  of  America.  Leases  film 
to  licensed  film  exchanges  only. 

Sicania  Film  Factory,  45  Piazzi  Giuseppe  Verdi,  Palermo,  Italy. 
The  trademark  "Sicania." 

SociETE  CiNES.  Making  films  with  the  trademark  of  the  Wolf-and-Babes. 
Office  address,  11  Rue  Saint  Augustin,  Paris,  France.  Studios  in  France  and 
in  Italy. 

SoLAX  Company,  147  Fourth  Avenue,  New  York,  N.  Y.,  factory  and 
studio  at  Flushing,  Long  Island.  Making  picture  film  under  the  name  "Solax." 
Sold  only  through  the  M.  P.  Distributing  &  Sales  Co. 

Sunny  South  Film  Company,  Rhodes  Building,  Atlanta,  Ga. 

Thanhouser  Company,  manufacturing  with  the  trademark  "TCO." 
Offices  and  studio  at  New  Rochelle,  N.Y.  Films  sold  through  the  Distribut- 
ing and  Sales  Company. 


281 


206  THE  MOTION  PICTURE 

Tyler  Film  Company,  Ltd.,  London,  England,  makers  of  film  pictures 
under  the  trademark,  "T.  F.  C." 

Unitas  Film  Manufacturing  Company,  Torino,  Italy.     . 

Charles  Urban  Trading  Company,  film  publishers,  Urbanora  House, 
89  Wardour  Street,  London,  W.,  England.  "Urban"  and  "Urban-Eclipse" 
black-and-white  films  and  "Urban-Smith"  Kinemacolor  films. 

The  Vitagraph  Company  of  America,  116  Nassau  Street,  New  York, 
N.  Y.  Studio  on  Long  Island.  Licensed  under  the  patents  controlled  by  the 
Motion  Picture  Patents  Company  of  America.  Film  leased  to  licensed  film 
exchanges  only.  Trademark,  the  letter  "V"  surmounted  by  an  eagle  with 
spreading   wings. 

"Warwick  Trading  Company,  Ltd.,  113  Charing  Cross  Road,  London, 
W.  C,  England. 

"Wrench"  Films,  50  Gray's  Inn  Road,  London,  W.  C,  England. 

Yankee  Film  Company,  344  East  32nd  Street,  New  York,  N.  Y.  Making 
picture  film  under  the  trade  name  of  "Uncle  Sam  Films"  and  the  sign  of  Uncle 
Sam  in  costume  holding  a  white  "Y."  Films  sold  through  the  M.  P.  Distribut- 
ing &  Sales  Co. 


282 


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PHOTOGRAPHY 

THEORY 

The  making  of  photographs  may  be  divided  into  three  very 
general  or  theoretical  steps:  First,  producing  an  image  of  the  scene 
or  object  of  which  it  is  desired  to  make  a  photograph.  Second, 
receding  the  image  in  permanent  form.  Third,  copying,  multiply- 
ing, or  reproducing  the  image  into  as  many  finished  photographs 
as  may  be  desired. 

Any  of  these  steps  may  be  accomplished  in  any  of  several  ways 
by  the  photographer,  according  to  the  results  which  he  desires  to 
attain,  or  according  to  the  limitations  of  the  apparatus  which  he  has 
available.  Thus,  images  usually  are  formed  for  photography  by 
means  of  a  lens;  but  if  the  photographer  has  no  lens,  or  arbitrarily 
decides  not  to  use  it,  he  may  form  an  image  without  it.  The  image 
formed  being  composed  of  rays  of  light  of  different  strengths,  the 
second  step  taken  by  placing  in  the  image  a  surface  bearing  a 
substance  which  is  sensitive  to  light  and  which  will  be  discolored  to 
different  degrees  by  the  different  strengths  of  the  different  rays  and  by 
the  spots  of  light  formed  by  them  in  the  image.  Tliis  second  step 
produces  the  record  of  the  image,  and  from  it  a  number  of  finished 
photographs  may  be  produced  in  a  manner  not  altogether  unlike 
the  production  of  several  thousand  newspapers  by  a  printing  press 
after  the  typesetters  have  made  ready  the  printing  tj'pes  and  the 
engravers  have  made  ready  the  printing  picture  plates. 

MECHANICAL  DETAILS 

Camera.  The  camera  is  a  dark  box  within  which  the  photog- 
rapher forms  the  image.  The  light  is  admitted  to  the  camera  dur- 
ing the  making  of  the  photograph,  and  in  most  cameras  during  the 
preparation  for  the  photograph  and  the  proper  adjustment  of  the 
camera  for  forming  the  desired  image. 

Pin=hole  Image.  To  understand  just  how  the  image  is  formed 
in  the  camera,  perform  the  following  experiment: 

Copyright,  1911,    by  American    School  of  Correspondence. 


11 


2  THE  MOTION  PICTURE 

Take  a  paper  box,  white  inside,  about  the  size  of  a  shoe  box. 
Remove  half  of  the  Hd.  In  the  middle  of  one  end  of  the  box,  punch  a 
hole  with  a  darning  needle,  making  a  hole  about  -e  inch  in  diameter, 
with  smooth  edges.  Place  the  box  in  the  window,  the  hole  toward 
the  street,  and  with  the  half-lid  on  that  part  of  the  top  of  the  box 
near  the  street.  Draw  the  shade  to  the  top  of  the  box,  and  obscure 
the  remainder  of  the  window  as  well  as  other  windows  of  the  room 
so  that  the  only  light  received  will  be  through  the  small  hole  in  the 
end  of  the  box — the  pin-hole  as  it  is  termed  in  photography,  Fig.  1. 
On  the  inside  of  the  box,  at  the  end  opposite  the  pin-hole,  there  will 


BOX 

I      /MA6E 


^ 


Fig.  1.     Pin-hole  Image 


be  formed  an  image  of  the  objects  upon  the  opposite  side  of  the 
street.  The  image  may  be  viewed  through  the  open  half  of  the 
top  of  the  box,  and  will  be  seen  a  living  image,  in  natural  colors,  but 
inverted,  its  size  depending  upon  the  length  of  the  box.  Try  it  with 
boxes  of  different  lengths,  or  moving  a  white  card  in  the  box. 

Inverted  Image.  The  reason  why  the  image  is  inverted  is  shown 
in  Fig.  2,  in  which  the  object,  the  pin-hole,  and  the  image  are  rep- 
resented. All  rays  of  light  pass  in  straight  lines,  and  all  the  light 
from  the  top  of  the  tree  at  the  right  which  gets  through  the  pin-hole 
passes  in  a  straight  line  to  the  bottom  of  the  image  at  the  left;  light 
from  the  bottom  of  the  tree  goes  to  the  top  of  the  image.  This  is 
true  for  every  point  of  the  view;  hence,  the  view  is  inverted  in  the 
image. 


12 


PHOTOGRAPHY  3 

Now  with  a  lead  pencil,  enlarge  the  pin-hole  until  the  pencil 
can  pass  through.  Note  the  difference  in  the  image.  It  is  blurred. 
Each  point  in  the  scene  makes  a  spot  in  the  image  as  large  as  the 
hole  in  the  box;  yet  the  image  as  a  whole  is  brighter.  A  spectacle 
lens  placed  over  the  hole  in  the  box  might  make  the  image  sharp, 
but  at  tliis  point  the  pin-hole  experiment  may  be  abandoned  and 
the  working  of  the  photographer's  camera  as  it  is  commercially 
used  may  be  taken  up  to  complete  the  study  of  the  first  step  in  theory, 
or  the  formation  of  the  image  in  practice. 

Buying  a  Camera.  The  learner  who  intends  either  to  make 
moving  pictures  after  learning  still  photography,  or  to  make  good 
still  photographs,  must  first  purchase  a  tripod  camera.  Concern- 
ing the  work  of  hand  cameras,  a  photographer  handling  amateur 
work  at  a  holiday  resort  is  quoted  as  saying  that  of  more  than  a 


Fig.  2.     Inverted  Image 

thousand  negatives  developed  by  him  in  one  summer  there  were 
not  twenty  good  pictures  and  hardly  forty  good  negatives.  Only 
with  the  tripod  camera  can  the  photographer  know  what  he  is  doing 
and  then  operate  his  camera  intelligently  and  successfully. 

The  camera  purchased  for  intelligent  work  must  be  either 
4-inch  by  5-inch  size,  with  bellows  draw  of  12  inches  or  more,  or 
5-inch  by  7-inch  size,  with  bellows  draw  of  15  inches  or  more.  Smaller 
than  4  by  5  is  too  small  for  intelligent  work  by  the  ambitious  amateur, 
and  larger  than  5  by  7  is  too  heavy  for  amateur  work.  In  either 
case,  the  camera  should  have  a  single  swing,  and  must  have  a  rising 
front  and  holders  for  glass  plates;  it  may  have  a  convertible  rectilinear 
lens  or  a  more  expensive  convertible  anastigmatic  lens,  but  in  either 
case  the  lens  must  be  convertible  and  should  be  equipped  with  an 
iris  diaphragm  and  an  automatic  shutter.  The  usefulness  of  each 
of  these  features  will  appear  as  the  operation  of  the  camera  is  de- 


13 


4  THE  MOTION  PICTURE 

scribed.  A  camera  4  by  5  may  be  had  at  a  catalogue  price  of  S25.00 
or  more,  and  a  camera  5  by  7  at  $33.00  or  more,  filling  all  require- 
ments. Two  extra  plate-bolders  should  be  bought,  that  six  plates 
may  be  carried  into  the  field.  A  tripod  and  focusing  cloth  complete 
the  necessary  field  equipment,  with  the  possible  addition  of  an 
exposure  meter. 

Construction  of  Camera.  The  body  of  the  camera  consists 
of  the  back  frame,  the  front  frame,  and  a  base.  The  base  connects 
the  back  and  front  frames  and  upon  it  the  front  frame  moves  as 
upon  a  track.  Connecting  the  back  and  the  front  is  the  bellows. 
The  front  carries  the  lens,  mounted  upon  a  detachable  lens  board; 
the  back  carries  the  ground  glass  or  focusing  screen,  and  permits 
the  insertion  of  one  of  the  plate-holders  in  such  a  manner  that  when 
the  plate-holder  is  inserted  the  ground  glass  is  pushed  out  of  its 
normal  position  and  the  glass  plate  within  the  holder  occupies  the 
position  formerly  held  by  the  ground  glass. 

Place  the  camera  in  the  window  as  the  shoe  box  was,  and  open 
shutter  and  diaphragm.  The  shutter  is  opened  by  setting  its  index 
to  "T,"  or  "Time,"  and  operating  it  with  the  rubber  bulb.  The 
diaphragm  is  opened  by  setting  its  index  to  the  lowest  number, 
probably  8.  Extend  the  bellows  until  a  sharp  image  is  seen  upon 
the  ground  glass.  Look  at  the  ground  glass,  not  through  it.  If  the 
back  of  the  camera  and  the  operator's  head  are  covered  with  the 
focusing  cloth,  it  will  not  be  necessary  to  darken  the  room  for  this 
experiment.  By  moving  the  camera  front  to  different  positions, 
it  will  be  observed  that  the  image  is  sharp  in  only  one  position. 
This  is  the  position  of  focus  of  the  lens. 

Lenses.  The  lens  is  composed  of  a  barrel  carrying  the  shutter 
and  iris  diaphragm  in  its  middle  portion  and  carrying  at  each  end 
a  "lens  cell,"  or  metal  mount,  into  which  the  glasses  of  the  lens 
are  fixed.  The  glasses  may  be  removed  from  the  lens  barrel  by  un- 
screwing their  mounts  from  the  barrel.  Unscrew  the  front  lens  ceP 
and  extend  the  bellows  until  the  image  upon  the  ground  glass  is 
sharp  again.  This  is  the  focus  for  the  "back  combination,"  or  that 
cell  which  still  remains  in  the  lens.  The  bellows  is  longer,  the  image 
is  larger.  Sometimes  the  front  combination  of  the  lens  is  of  still 
longer  focus  than  the  back  combination,  giving  an  image  still  larger, 
but  with  still  longer  extension  of  the  bellows. 


14 


PHOTOGRAPHY  5 

Replace  the  lens  cells.     Select  in  the  image  a  distant  object, 
such  as  a  chimney  500  feet  away.    Focus  sharply  upon  it  by  moving 


Fig.   3.     Pin-hole  without  Lens 

the  camera  front  until  the  cnimney  is  sharp.  Note  a  near  object,  a 
house  or  tree  within  50  feet;  it  is  not  sharp.  To  focus  sharply  upon 
the  near  object,  it  is  necessary  to  extend  the  bellows  slightly.  Now 
the  distant  object  is  not  sharp.  Try  to  place  the  focus  between  the 
two;  then  reduce  the  iris  diaphragm  to  32  or  even  64.  Now  both 
distant  and  near  objects  are  sharp. 

Remove  both  lens  cells.  Shut  the  iris  diaphragm  as  close  as 
it  will  move.  Look  upon  the  ground  glass;  the  image  of  the  shoe 
box  is  there.    Move  the  bellows  to  different  lengths;  the  size  of  the 


Pin-hole  with  Lens 


pin-hole  image  is  changed  but  it  is  in  as  good  focus  in  one  place  as 
another.  The  pin-hole  image  has  no  definite  length,  and  everything, 
near  and  far,  is  in  focus.    Replace  the  lens  cells.    With  the  diaphragm 


15 


6  THE  MOTION  PICTURE 

still  at  its  smallest  size,  the  lens  makes  the  image  sharper,  but  a 
position  may  be  found  at  which  everything  seems  to  be  in  focus, 
both  near  and  far  objects.  This  is  called  the  condition  of  universal 
focus. 

Focal  Length.  The  distance  from  the  ground  glass  to  the  center 
of  the  lens  when  the  image  is  in  focus  upon  the  glass,  is  called  the 
focal  length  of  the  lens,  and  usually  is  expressed  in  inches.  The 
focal  length  of  the  two  combinations  or  cells  of  the  lens  when  used 
together  is  shorter  than  the  focal  length  of  either  of  them.  With  a 
5  by  7  lens,  the  complete  lens  should  have  a  focal  length  of  7  inches 
or  a  little  more;  each  of  the  combinations  alone  should  be  about  12 
inches,  or  one  of  them  about  11  and  the  other  about  14  inches. 


Fig.   5.     Lens  Image 

Figs.  3  and  4  show  the  action  of  the  lens.  The  glass  of  the 
lens  bends  the  rays  of  light,  which  proceed  from  a  point  in  the  sub- 
ject until  they  reach  the  lens  and  then  are  bent  by  the  lens  to  approach 
until  again  they  meet  in  a  point,  making  a  sharjjer  spot  of  light  on 
the  ground  glass  in  Fig.  4  with  the  lens  than  in  Fig.  3  where  the 
pin-hole  without  the  lens  is  shown.  This  is  true  of  all  points  of  the 
subject,  as  shown  in  Fig.  5. 

The  distance  from  the  lens  to  the  place  where  the  ray  again 
comes  to  a  point  depends  upon  the  strength  of  the  lens  in  bending 
the  rays,  and  this  distance  is  the  focal  length  of  the  lens.  In  Fig.  6 
the  back  lens  cell  alone  bends  the  light  to  bring  it  to  a  focus;  while 
in  Fig.  7  both  front  and  back  lens  cells  bend  the  light,  one  after  the 


16 


PHOTOGRAPHY  7 

other,  bending  it  to  a  much  greater  extent,  bringing  it  to  a  focus  in 
a  shorter  distance,  giving  a  shorter  focus  or  shorter  lens  length, 
and  producing  of  course  a  smaller  image  on  the  ground  glass. 


Fig.  6.     Long-Focus  Lens 

Measuring  Length.  Without  a  camera,  a  lens  may  be  measured 
approximately  by  focusing  the  image  of  the  sun  upon  any  convenient 
surface,  such  as  a  small  card,  then  measuring  with  a  iiiler  the  distance 
from  the  middle  of  the  lens  barrel  to  the  card.  With  a  camera, 
focus  upon  a  very  distant  object,  and  measure  from  the  middle  of 
the  lens  barrel  to  the  ground  glass.  A  more  accurate  method,  where 
a  camera  of  sufficiently  long  bellows  is  available,  is  to  focus  upon 
any  close  object  until  the  image  on  the  ground  glass  is  exactly  the 
size  of  the  object.  Measure  the  distance  between  the  object  and  the 
ground  glass  and  divide  by  four.  To  make  this  measurement  con- 
veniently, cut  two  slips  of  paper  of  equal  length  and  attach  one  to 
the  ground  glass  and  the  other  to  the  glass  of  the  window.  Place 
the  camera  on  a  table  where  it  may  slide  toward  the  window  to 
change  the  size  of  the  image.  Use  the  largest  diaphragm  opening. 
When  the  edges  of  the  image  of  the  slip  of  paper  are  sharp  and 
when  the  image  on  the  ground  glass  and  the  slip  of  paper  on  the 
ground  glass  are  of  the  same  length,  the  distance  between  the  object 
and  the  image  will  be  four  times  the  focal  length  of  the  lens. 


Fig.  7.     Short-Focus  Lens 


Position  of-  Diaphragm  Opening.  The  influence  upon  the 
image  of  the  diaphragm  opening,  or  "stop,"  and  of  its  position  with 
reference  to  the  lens  is  shown  in  Figs,  8,  9,  and  10.  In  each  of  these 
figures,  there  are  shown  a  photographic  subject  composed  of  straight 


17 


8  THE  MOTION  PICTURE 

lines,  a  lens,  a  stop  opening,  and  an  image  of  the  subject  formed  by 
the  lens  through  the  diaphragm.  In  each  figure,  the  subject  and 
the  image  are  shown  in  a  front  view,  while  the  lens  and  diaphragm 


Fig.   8.     Barrel  Distortion 

are  shown  in  side  view,  or  rather  in  sectional  view  as  though  cut 
through  the  middle. 

In  Fig.  8,  the  diaphragm  opening  is  in  front  of  die  lens,  between 
the  lens  and  the  subject  to  be  photographed.  The  result  is  a  bend- 
ing of  all  the  straight  lines  of  the  image,  drawing  the  ends  of  the 
lines  toward  the  middle  line  of  the  image,  both  horizontally  anrl 
vertically.  This  form  of  distortion  is  called  barrel  distortion.  In 
Fig.  9,  the  diaphragm  opening  is  behind  the  lens,  between  the  lens 
and  the  image.  This  results  in  bending  the  lines  of  the  image  in  the 
opposite  direction,  and  produces  what  is  called  a  pin-cushion  dis- 
tortion. In  Fig.  10,  a  double  lens  is  shown,  the  glasses  of  the  lens 
l)eing  divided  into  two  cells  with  the  diaphragm  or  stop  between 
them.  With  such  an  arrangement  the  pin-cushion  distortion  of  the 
front  lens  cell  is  just  balanced  by  the  barrel  distortion  of  the  back 
lens  cell,  and  the  resulting  image  has  all  its  lines  straight.  Such  a 
lens  is  called  a  rectilinear  lens.    To  avoid  distortion,  the  diaphragm 


Fig.  9.     I'in-cushion  Distortion 


must  be  placed  between  the  two  cells  at  the  proper  distance  from 
both.  Of  the  two  forms  of  distortion  shown  in  Figs.  8  and  9,  the 
barrel  distortion  is  the  less  objectionable,  and  when  a  single  lens 
is  used,  it  should  be  placed  in  the  back  end  of  the  lens  tube,  even 


18 


PHOTOGRAPHY  9 

though  it  be  the  front  cell  of  the  complete  lens.  The  single  lens 
senses  satisfactorily  for  landscape  and  portrait  work,  in  either  of 
which  it  may  be  said  there  are  no  straight  lines      In  photographing 


10.     Rectilinear  Lens 


architectural  subjects,  where  the  straight  lines  of  the  sides  of  build- 
ings are  near  the  edge  of  the  plate,  and  in  interiors,  only  the  rec- 
tilinear lens  may  be  used  if  passable  results  are  desired. 

Focusing.  Bringing  the  desired  image  into  focus  is  controlled 
by  the  position  of  the  ground  glass  at  the  proper  distance  from 
the  lens,  and  also  by  the  size  of  the  opening  in  the  diaphragm  or 
stop.  Every  point  in  the  image  is  formed  by  a  mass  of  light  rays 
which  is  conical  in  form,  as  big  as  the  stop  opening  at  the  lens,  and 
tapering  down  to  a  point  at  or  near  the  groimd  glaas.  \Mien  the 
exact  tip  of  this  cone  is  upon  the  surface  of  the  ground  glass,  the 
point  is  in  focus  and  sharp  in  the  image.  \Mien  the  tip  of  the  cone 
is  a  little  behind  or  in  front  of  the  ground  glass,  the  point  is  slightly 
blurred,  but  if  not  too  much  blurred  it  may  be  said  to  be  still  in 
focus.  The  amount  of  blur  depends  upon  the  size  of  the  cone  at 
the  place  where  the  ground  glass  is  met.    Fig.  11  shows  a  lens  with 


Fig.    11.     Lens  without  Diaphragm  Stop 

a  large  stop  opening.  The  point  B  of  the  subject  is  in  focus  at  the 
point  h  of  the  image;  the  point  A  of  the  subject  is  in  focus  at  the  point 
a  of  the  image.  With  the  ground  glass  at  the  vertical  line,  through 
a  the  point  A  will  be  shaip  and  the  point  B  will  be  blurred  in  the 
image.  With  the  ground  glass  at  the  vertical  line,  through  h  the 
point  B  will  be  .sharp  in  the  image  and  the  point  A  will  be  blurred. 


19 


10 


THE  MOTION  PICTURE 


Fig.  12  shows  the  same  system  with  a  smaller  stop  opening.  The 
cone  from  the  point  A  is  smaller  where  it  crosses  the  vertical  line 
through  b,  hence  the  blur  will  be  less,  and  the  focus  more  nearly 


Fig.  12.     Lens  with  Diaphragm  Stop 

correct.  With  the  ground  glass  midway  between  the  points  a  and  b, 
both  will  be  slightly  blurred,  but  the  blur  will  be  less  with  the  smaller 
top  opening,  Fig  12  "Depth  of  field"  in  an  image  refers  to  the 
•listance  from  the  nearest  object  in  focus  to  the  farthest  object  in 
focus.  With  the  smaller  stop  opening,  the  depth  of  field  is  increased. 
Spherical  Aberration.  Lenses  ground  by  machines  present 
spherical  surfaces  upon  both  sides,  although  not  of  concentric 
spheres.  Such  a  lens  bends  a  ray  of  hght  to  a  greater  degree  when 
the  ray  passes  through  the  lens  near  the  edge  than  when  the  ray 
passes  through  the  lens  near  the  center.  This  is  illustrated  in  Fig. 
13.  By  the  greater  bending,  the  rays  from  the  object  C  which  pass 
near  the  edge  of  the  lens  are  brought  to  focus  on  the  line  c,  while 
those  through  the  central  portion  are  brought  to  focus  upon  the 
line  c'.  This  defect  in  the  lens  is  reduced  by  the  use  of  a  lens  which 
is  meniscus  in  form,  having  one  convex  and  one  concave  surface, 
as  illustrated  in  Fig.  14.  It  is  reduced  also  by  the  use  of  a  smaller 
stop  opening,  as  illustrated  in  Fig.  15. 


Fig.   13.     Spherical  Aberration  in  Convex  Lens 

Chromatic  Aberration.  The  light  rays  of  different  colors  are 
affected  to  different  degrees  by  the  refractive  attribute  of  the  glass 
of  the  lens.  The  violet  light  is  bent  through  a  greater  angle  than 
the  yellow  light,  and  the  remaining  colors,  as  well  as  the  ultra-violet 
rays,  are  changed  in  direction  through  different  angles.     This  pro- 


20 


PHOTOGRAPHY 


11 


duces  the  effect  of  bringing  the  different  colors  to  focus  at  different 
distances  from  the  photographic  lens  of  the  simplest  type,  viz,  of 
a  single  meniscus  piece  of  glass.    The  principle  involved  is  the  same 


Fig.    14.     Spherical  Aberration  in  Meniscus  Lens 

as  that  by  which  a  single  ray  of  white  light  is  separated  by  a  prism 
into  its  elementary  colors,  a  band  of  colored  rays  being  secured  by 
the  separation  of  the  single  white  ray. 

The  effect  in  a  photographic  lens  is  shown  in  Fig.  IG.  The  ray 
of  white  light  from  the  point  D  of  the  subject  is  brought  to  focus  in 
several  different  points  according  to  the  colors  into  which  the  light 
is  separated.  The  yellow  light  is  brought  to  focus  at  the  line  d, 
while  the  violet  light  is  brought  to  focus  on  the  line  d'.  Of  all  the 
colors  composing  white  light,  yellow  affects  the  eye  to  the  greatest 
degree  and,  consequently,  in  focusing  the  camera  by  looking  at 
the  image  upon  the  ground  glass,  the  yellow  light  is  appreciated 
by  the  eye  and  the  ground  glass  is  brought  to  that  position  in 
which  the  yellow  rays  are  in  focus.  At  the  same  time,  the  red 
and  blue  rays  are  so  nearly  in  focus  that  they  unite  to  give  the  appear- 
ance of  white  light  in  focus  upon  the  screen.  When  the  sensitive 
plate  is  placed  in  the  camera,  occupying  the  position  of  the  ground 
glass,  and  the  light  is  permitted  to  fall  upon  it  through  the  lens, 


Fig.   15.     Spherical  Aberration  Reduced  by  Diaphragm  Stop 

the  conditions  of  appreciation  of  the  light  are  changed.  The  sensitive 
plate  is  most  sensitive  to  the  blue — the  violet  antl  the  ultra-violet 
rays — and  these  are  not  in  focus  upon  its  surface. 

Outside  of  the  lens,   the  remedies  for  color  aberration  are  to 
focus  through  a  blue  glass,  to  use  a  blue  ground  glass,  or  to  wear 


ai 


12 


THE  MOTION  PICTURE 


blue  spectacles.  Another  method  is  to  know  the  specific  correction 
for  the  lens  used  and  to  move  the  ground  glass  the  proper  distance 
toward  the  lens  after  focusing  upon  the  yellow  image. 


Fig.   16.     Chromatic  Aberration 

Within  the  lens,  the  correction  may  be  made  by  uniting  two 
pieces  of  glass  of  different  refractive  powers,  one  lens  being  ground 
"positive,"  or  thicker  in  the  middle  than  in  the  edges,  and  th* 
other  one  being  ground  "negati\'e,"  or  thinner  in  the  middle  than 
in  the  edges.  Two  of  the  surfaces  have  the  same  curvature  and  the 
two  lenses  when  completed  are  cemented  together,  Fig.  17.  Even 
the  cheapest  classes  of  lenses  are  thus  made  double,  except  in  the 
smallest  sizes  and  when  of  short  focus.  A  rectilinear  lens,  composed 
of  two  single  lenses,  each  of  which  is  corrected  for  chromatic  aberra- 
tion, would  present  a  combination  of  glasses  such  as  is  shown  in 
section  in  Fig.  18  or  Fig.  19. 

Astigmatism.  The  meaning  of  this  word  is  icith  no  'point.  Its 
meaning  as  applied  to  a  photographic  lens  is  that  the  lens  has  not 
the  ability  to  bring  to  a  focus  at  a  point  all  of  the  rays  proceeding 
from  a  point  in  the  subject.  Thus  a  point  in  the  subject  becomes 
something  else  in  the  image.  The  bundle  of  rays  passing  from  a 
point  in  the  subject  and  through  the  stop  opening  takes  the  form 


Fig.  17.     AcliTomatic  Lens 


shown  in  Fig.  20.  The  best  focus  is  obtained  by  placing  the  ground 
glass  at  the  line  6,  where  the  point  takes  the  form  of  a  cross.  When 
tiie  ground  glass  is  at  the  line  a  nearer  the  lens,  the  point  takes  the 
form  of  a  short  radial  line,  or  ellipse,  with  its  longer  axis  radial  from 


22 


PHOTOGRAPHY 


13 


the  center  of  the  image;  when  the  ground  glass  is  at  the  hne  c  farther 
from  the  lens,  the  point  takes  the  form  of  a  short  arc  about  the  center 


Fis 


Fig.  19. 


Achromatic  Rectilinear  Lenses 


of  the  image,  or  of  an  approximate  ellipse  of  which  the  shorter  axis 
is  radial  and  the  longer  axis  is  an  arc  instead  of  a  straight  line. 

The  remedy  for  astigmatism   lies  in   the  construction   of  the 
lens,   and   lenses   which   are  corrected   for  astigmatism   are  called 


Fig.  20.     Bundle  of  Raj's  with  Astigmatism 


anastigmals.  Two,  three,  four,  and  even  five  pieces  of  glass  are 
used  sometimes  in  producing  single  lenses  free  from  astigmatism, 
chromatism,  and  spherical  aberration.     Fig.  21  shows  a  single  lens 


Fig.  21. 


Fig.   22. 
Anastigmatic  Lens  Combinations 


of  four  glasses.    Fig.  22  shows  the  glasses  of  a  aouble,  or  rectilinear, 
lens  of  two  single  lenses  having  eight  glasses  in  all. 

The  art  of  the  lens  maker  is  a  delicate  one.     A  lens  should  be 
bought  and   used   by   the  photographer,   and   not   tampered   with. 


23 


14  THE  MOTION  PICTURE 

A  good  lens  should  be  kept  in  a  dust-proof  case  when  not  in  use. 
It  may  be  brushed  with  a  soft  camel's-hair  brush  and  wiped  with  soft 
clean  tissue  paper  to  remove  dust— not  a  cotton  or  silk  rag,  which 
may  carry  grains  of  grit  to  scratch  the  surface  of  the  glass. 

Shutters.  AMien  the  camera  is  prepared  for  exposing  a  plate 
to  an  image,  the  lens  stands  as  a  window  in  the  front  of  the  camera. 
The  purpose  of  the  shutter  is  to  close  the  lens  window  until  the 
moment  for  exposure,  then  to  open  the  lens  and  again  to  close  it 
after  sufficient  amount  of  light  has  passed  through  to  impress  the 
image  upon   the  sensitive  plate. 

Cap.  The  simplest  of  shutters  is  the  cap,  which  is  a  shallow 
box  fitting  closely  over  the  front  of  the  lens  barrel.  For  exposures 
of  several  seconds  or  more  in  duration,  the  cap  offers  the  most  con- 
venient means,  while  for  exposures  of  less  than  one-half  second,  the 
cap  can  hardly  be  removed  and  replaced  cjuickly  enough,  and  some 
sort  of  automatic  opening  and  closing  device  should  be  used. 

Leaf.  The  leaf  shutter  consists  of  hinged  leaves  which  meet 
and  overlap  to  close  the  lens  opening.  They  are  forced  open  by  a 
spring  and  forced  closed  by  a  spring.  An  exposure  of  as  brief  a 
space  as  yI^  second  is  feasible  with  the  leaf  shutter;  and  some  shut- 
ters are  advertised  to  make  even  shorter  exposures.  By  the  addition 
of  an  air  piston,  the  closing  of  the  shutter  may  be  delayed  until  after 
the  piston  has  completed  a  predetermined  travel,  thus  giving  an 
exposure  longer  than  the  shortest  of  which  the  shutter  is  capable. 
The  usual  "automatic"  leaf  shutter  may  be  "set"  before  ex-posure 
to  give  an  exposure  of  from  one  second  to  j\o  second.  The  shutter 
may  be  adjusted  also  to  hold  the  lens  open  until  released.  Exposures 
longer  than  one  second  may  be  made  by  the  "time"  adjustment, 
opening  the  shutter  at  the  beginning  of  exposure  and  closing  it  after 
the  proper  lapse  of  time,  as  in  the  case  of  exposure  with  the  cap. 
The  leaf  shutters  usually  work  between  the  lenses,  near  the  diaphragm. 

Curtain.  The  curtain  shutter  consists  of  two  curtains  on  spring 
rollers  inside  the  camera  just  behind  the  lens.  When  the  shutter 
is  adjusted  for  exposure,  one  of  the  curtains  is  in  front  of  the  lens; 
the  other  is  above,  rolled  up.  Upon  release  of  the  shutter,  the  lower 
curtain  rolls  down,  opening  the  lens;  after  the  desired  lapse  of  time, 
the  upper  curtain  unrolls  and  passes  down,  stopping  over  the  lens 
and  closing  it. 


94 


PHOTOGRAPHY  15 

Focal  Plane.  The  focal  plane  of  the  camera  is  the  position 
of  the  image  formed  by  the  lens.  When  ready  for  an  exposure,  the 
sensitive  plate  is  located  in  the  focal  plane.  The  focal-plane  shutter, 
which  is  a  curtain  just  in  front  of  the  plate,  is  so  called  because  it  is 
placed  as  near  to  the  plate  as  possible  and,  therefore,  near  the  focal 
plane  of  the  camera.  The  curtain  has  a  slit  which  may  be  adjusted 
in  width  or  it  has  several  slits  of  different  widths,  ^^^len  released 
the  curtain  rolls  without  stopping,  and  the  length  of  time  during 
which  the  light  is  permitted  to  shine  upon  the  plate  is  determined 
by  the  speed  of  the  curtain  and  by  the  width  of  the  slot.  With  a 
shutter  of  this  type,  exposures  as  short  as  y-g^o  ir  second  may  be  given. 
The  shutter  is  available  equally  for  longer  automatic  exposures  and 
for  time  exposures. 

Testing.  An  automatic  shutter  has  a  scale  for  setting  the  speed 
of  the  shutter,  usually  marked  1,  2,  5,  25,  100,  meaning,  respectively, 
1  second,  §  second,  \  second,  ^V  second,  and  y^o  second.  The  ex- 
posure given  to  the  plate  is  not  always  true,  however,  to  the  value 
indicated  by  the  scale  of  the  shutter.    The  method  of  test  is: 

Photograph  with  the  automatic  shutter  at  one  of  its  settings  an 
object  Tnoving  at  a  known  speed;  then  calculate  the  length  of  time 
of  the  exposure  from  a  measurement  of  the  amount  of  movement  visible 
in  the  photograph.  The  distance  moved  in  the  photograph  is  to  the 
distance  moved  by  the  object  during  the  exposure  as  the  focal  length 
of  the  lens  is  to  the  distance  of  the  lens  from  the  object.  When  the 
distance  moved  by  the  object  and  the  speed  of  the  object  is  known,  the 
time  required  to  move  through  that  distance  may  be  knoion,  and  that 
is  the  actual  exposure  of  the  shutter  for  the  speed  setting  under  which 
the  test  was  made. 

A  wheel  driven  at  a  constant  and  known  speed  may  carry  a 
mirror  on  its  face  near  its  edge,  the  mirror  reflecting  the  light  of  the 
sun  or  of  an  arc  lamp  into  the  lens.  In  this  case,  the  distance  and 
focal  length  need  not  be  measured;  the  angle  of  the  arc  which  the 
revolving  mirror  makes  upon  the  plate  while  the  shutter  is  open  will 
give  the  duration  of  the  exposure  for  the  shutter  setting  under  which 
the  test  was  made. 

Under  test,  a  new  fabulously  high-priced  leaf  shutter  showed 
an  accuracy  of  only  60  per  cent.  Another  cheap  leaf  shutter  gave 
exactly  the  same  length  of  exposure  for  its  ^\  marking  and  for  its 


25 


IG  THE  MOTION  PICTURE 

j^iy  marking,  the  exposure  being  ^\  second  for  either  of  them.  A 
fair  shutter  test  easily  made  is  as  follows: 

With  stop  f/ 11  and  shutter  speed  gV  expose  a  plate,  and  with  stop 
f/64  and  cap,  time,  or  bulb  exposure,  give  t  and  \\  seconds  as  accurately 
as  possible.  These  exposures  are  nearly  equal,  and  when  developed 
in  the  same  tray  or  tank  the  plates  should  be  alike. 

The  speed  markings  of  a  new  shutter  may  be  accepted  as  cor- 
rect; the  medium  speeds  ^  and  2^5,  which  are  used  most  by  the  ama- 
teur, are  likely  to  be  nearly  accurate.  The  shorter  exposures  are 
likely  to  be  too  long;  the  longer  ones  are  likely  to  be  too  short.  An 
old  or  second-hand  shutter  should  be  tested  for  speed  before  good 
work  is  attempted  with  it. 

Plate=Holder.  For  experimental  work  for  the  purpose  of  gain- 
ing a  knowledge  of  photography  sufficient  for  the  making  of  motion 
pictures  or  good  still  pictures,  glass  dry  plates  should  be  used.  Cut 
films  or  roll  films  may  be  adopted  later,  but  the  more  reliable  glass 
dry  plate  should  be  used  by  the  beginner. 

The  plate-holder  has  two  draw  slides,  and  when  each  is  drawn 
there  is  revealed  a  set  of  clamps  for  holding  a  glass  plate  inside  the 
holder.  The  handle,  or  edge,  of  each  slide  is  white  on  one  side  and 
black  on  the  other.  In  the  dark  room,  by  dim  ruby  light,  place  a 
glass  plate  in  each  side,  with  the  film,  or  dull,  side  facing  out,  and 
replace  the  slides,  white  side  out.  The  plate-holders  should  be 
numbered  on  each  side,  the  first  holder  being  1  on  one  side  and  2 
on  the  other;  the  second  holder  being.  3  on  one  side  and  4  on  the 
other,  etc.  \Mien  exposing  plates,  always  expose  first  the  No.  1 
side  of  the  first  holder,  or  the  No.  1  plate,  then  the  No.  2  plate,  then 
No.  3,  etc.  Upon  returning  to  the  dark  room  for  development, 
the  subjects  upon  each  plate  will  be  remembered  by  remembering 
the  order  of  the  exposures,  and  it  is  likely  that  only  one  exposure 
will  have  been  made  upon  each  plate.  Without  some  system  for 
exposing  plates  in  order,  it  is  possible  that  upon  development  one 
plate  will  show  a  ship  sailing  through  a  forest,  and  another  plate 
will  show  nothing  but  the  fog  of  an  imperfect  ruby  lamp. 

The  camera  is  so  arranged  that  the  ground  glass  may  be  removed 
and  the  plate  in  its  holder  substituted.  The  removal  of  the  ground 
glass  may  be  by  actually  taking  away  the  frame  which  holds  it, 
but  the  more  common  method  in  small  cameras  is  to  force  the  plate- 


i 


PHOTOGRAPHY  17 

holder  into  the  camera  in  front  of  the  ground-glass  frame,  the  ground- 
glass  frame  being  held  by  springs  which  yield  to  permit  the  plate- 
holder  to  enter.  \Mien  the  plate-holder  is  removed  subsequently, 
the  ground-glass  frame  automatically  resumes  its  proper  position  for 
focusing. 

Darkroom.  The  darkroom  is  a  room  which  is  not  merely  dusky, 
but  a  room  which  has  absolutely  no  white  light.  It  may  have  red 
light  until  it  is  far  from  dark,  hence  "darkroom"  is  but  a  name. 
It  must  not  have  any  light  which  will  affect  the  sensitive  plate.  No 
daylight.  Windows,  doors,  and  transoms  must  be  examined  for 
cracks.  After  remaining  in  a  darkroom  for  a  few  minutes,  cracks 
will  be  seen  which  were  not  noticed  at  first.  A  bathroom  at  night 
makes  a  desirable  darkroom  for  photographic  operations.  A  mov- 
able platform  across  the  tub  offers  a  work  table,  and  running  water 
is  convenient.  A  ruby  lamp  must  be  purchased.  If  a  satisfactory 
screen  is  made  for  the  window,  such  a  dark  room  may  be  used  during 
the  day.  No  white  light  must  get  to  the  plate  except  through  the 
lens  during  the  interval  of  exposure.  A  little  practice  enables  the 
photographer  to  load  his  plate-holders  by  touch  alone,  no  light  being 
needed.  This  enables  plate-holders  to  be  loaded  in  daytime  in  any 
closet  by  a  little  care  in  closing  the  cracks  around  the  door. 

A  convenient  darkroom  may  be  built  of  rough  boards  in  any 
corner  of  any  room,  basement,  attic,  or  bam,  the  cracks  being  care- 
fully closed  by  papering  inside  and  outside.  A  developing  shelf 
should  be  the  height  of  the  waist.  If  nmning  water  is  desired  in  the 
darkroom,  a  sink  should  be  convenient  to  the  developing  shelf,  but 
running  water  in  any  but  a  very  large  darkroom  is  an  objection 
rather  than  an  advantage.  In  the  wall  back  of  the  developing  shelf 
a  window  should  be  cut  into  which  a  sash  is  fitted  carrying  a  ruby 
glass.  Outside  of  the  darkroom,  on  a  shelf  or  bracket,  should  be 
the  lamp  for  furnishing  the  ruby  light,  so  placed  as  to  shine  through 
the  window.  Shelves  for  chemicals,  apparatus,  and  supplies  are 
outside  the  darkroom.  -The  darkroom  contains  nothing  but  a  de- 
veloping shelf,  a  door,  and  a  window  provided  with  removable  colored 
glass.  Dishwashing,  and  other  processes  not  necessarily  darkroom 
processes,  may  be  done  elsewhere. 

Routine  of  Camera  Operation.  Select  the  view.  Open  lens. 
Open  stop.    Focus  and  manipulate  the  camera  until  you  have  upon 


27 


18  THE  MOTION  PICTURE 

the  ground  glass  the  image  you  want,  no  more,  no  less.  Decide  upon 
the  stop  opening  to  be  used  and  the  length  of  exposure  to  be  given. 
Set  stop  opening.  Close  lens.  Adjust  shutter  to  selected  speed 
setting.  Insert  plate-holder.  Draw  dark  slide  of  plate-holder.  Re- 
lease automatic  shutter  or  otherwise  make  the  exposure.  Replace 
dark  slide  in  plate-holder,  black  out.  Remove  plate-holder  from 
camera. 

Practice  this  routine  without  plates  in  the  holders,  or  without 
drawing  the  dark  slide  from  the  plate-holder,  until  entirely  familiar 
with  alt  of  the  steps.  ^Nlany  plates  are  spoiled  by  drawing  the  dark 
slide  before  closing  the  lens,  or  by  failure  to  draw  the  dark  slide  at  all. 

PRODUCING  THE  IMAGE 

The  picture  is  made  upon  the  ground  glass  of  the  camera.  If 
the  photographer  has  the  patience  and  skill,  or  the  good  luck  as  an 
amateur,  to  secure  such  an  arrangement  of  his  subject  upon  the 
ground  glass  as  makes  a  good  picture  there,  then  the  mechanical 
and  chemical  processes  which  follow  will  merely  record  that  picture 
and  will  produce  a  pleasing  photograph  unless  the  record  should  be 
spoiled  by  accident.  The  view  selected  to  be  photographed  often 
is  forced  upon  the  photographer.  He  must  produce  a  picture  of 
this  house,  or  that  bridge,  or  of  the  children  of  the  family.  The 
motion-picture  camera  man  must  photograph  the  set  stage  or  such 
other  subject  as  the  producer  in  charge  may  direct.  Yet  the  control 
of  the  image  in  nearly  every  instance  is  so  completely  in  the  hands 
of  the  camera  operator  that  the  resulting  picture  is  better  or  worse 
as  he  is  careful  or  careless,  and  according  as  he  understands  the 
possibilities  of  his  camera  to  control  the  arrangement  of  the  details 
of  his  subject.  All  of  this  control  of  the  resulting  picture,  after  the 
voluntary  or  enforced  selection  of  the  principal  subject,  must  be 
exercised  before  the  exposure  of  the  sensitive  plate  or  film  is  made 
by  the  operation  of  the  lens  shutter.  After  the  lens  has  been  opened 
upon  the  subject,  transmitting  the  light  of  the  image  to  the  sensitive 
plate,  no  further  change  can  be  made  in  the  picture. 

The  making  of  the  picture,  that  is,  the  making  upon  the  ground 
glass  the  image  which  is  to  be  recorded  to  become  the  finished  photo- 
graph, may  be  divided  into  seven  points  for  consideration  t;nd  study, 
as  follows: 


28 


PHOTOGRAPHY  19 

(1)  The  selection  of  the  principal  object  to  be  photographed. 

(2)  The  selection  of  a  background  or  setting  for  the  principal 
object. 

(3)  The  lighting  or  direction  of  light  falling  iipon  the  subject 
as  a  whole. 

(4)  The  size  of  the  principal  object  in  the  image. 

(.5)  The  composition  and  balancing  of  principal  and  subordi- 
nate objects  in  the  image. 

(6)  The  prominence  of  the  background. 

(7)  The  avoidance  of  disagreeable  distortions  in  the  image. 
Principal  Object.     The  total  task  of  photographing    usually  is 

the  making  of  a  photograph  which  may  be  used  to  record  some  one 
object,  such  as  a  house,  a  tree,  a  flower,  a  person,  or  an  animal. 
Sometimes  it  is  merely  "a  pretty  scene,"  but  in  this  case  the  pho- 
tographer should  decide  upon  some  object  of  the  scene  to  form  the 
principal  object  of  the  picture.  He  should  give  such  prominence  to 
some  object  that  the  resulting  photograph  will  be  in  substance  a  pic- 
ture of  that  principal  object,  yet  will  embody  in  its  background  or 
scenic  setting  the  "pretty  scene"  which  it  was  desired  to  photograph. 
Right  at  the  beginning,  and  in  the  most  fundamental  of  all  of  the 
principles  of  picture  making,  the  camera  operator  has  the  power 
to  control  the  image,  to  make  or  spoil  the  picture,  even  though  com- 
manded by  an  outside  influence  as  to  his  general  subject.  Whether 
he  is  inspired  by  the  beauty  of  a  scene  to  make  a  photograph  of  it, 
or  whether  he  is  commanded  by  a  companion  or  by  an  employer  to 
make  a  photograph  of  it,  he  still  has  the  power  to  make  some  object 
a  principal  object,  to  hold  other  objects  subordinate  to  it,  and  to 
mold  the  whole  into  an  arrangement  in  the  image  on  his  ground  glass 
which  will  result  in  a  photograph  worthy  the  name  of  a  picture  when 
finished.  Each  picture  must  have  a  principal  object  or  it  is  at  best 
only  a  photographic  memorandum. 

Background.  In  portrait  work  in  a  studio,  the  backgrounds 
are  painted  as  desired,  and  brought  in  or  carried  out,  and  turned 
and  placed  as  needed.  And  for  scenic  w'ork  it  is  almost  the  same. 
Suppose  that  it  is  commanded  that  a  photograph  be  made  of  a  rose- 
bush in  blossom  in  the  front  yard  of  a  house.  If  the  house  would 
form  a  desirable  background,  set  up  the  camera  at  the  front  fence. 
If  the  front  fence  would  form  a  desirable  background,  photograph 


29 


20  THE  MOTION  PICTURE 

the  rosebush  from  the  house.  If  either  side  fence  is  better,  place  the 
camera  at  the  opposite  side  of  the  yard.  If  none  of  the  surround- 
ino-s  are  pleasing  as  background  objects,  there  is  still  the  possibility 
of  viewing  the  bush  from  above  so  that  the  grass  of  the  lawn,  and 
not  any  fence,  house,  or  other  object  is  included  as  a  background. 
This  view  may  be  had  from  the  top  of  a  stepladder,  from  an  upper 
window  of  the  house,  or  even  from  the  height  of  the  tripod  above  a 
porch  floor.  With  some  of  these  background  arrangements  surely 
the  resulting  picture  will  be  better  than  with  others.  Get  the  best  one, 
just  to  show  that  you  are  master  of  the  camera,  even  though  some  one 
else  dictates  what  your  principal  object  shall  be. 

AMien  photographing  persons  or  animals,  the  "principal  object" 
usually  may  be  brought  to  a  suitable  background.  When  photo- 
graphing a  house,  the  inclusion  in  the  image  upon  the  ground  glass 
of  a  little  more  of  the  foreground,  or  of  a  little  of  one  of  the  houses 
standing  at  one  side  of  the  "principal  object,"  or  of  a  tree  standing 
near,  partakes  of  the  fundamental  principle  of  the  selection  of  a  back- 
ground and  gives  the  camera  operator  some  power  to  make  his 
image  nearer  to  a  picture  and  farther  from  the  memorandum  type 
of  photograph. 

Lighting.  With  immovable  objects,  such  as  trees,  houses,  and 
rosebushes,  illuminated  by  the  sun,  the  photographer  has  two  methods 
of  controlling  his  lighting,  both  of  which  consist  merely  in  taking 
advantage  of  natural  conditions  by  the  selection  of  the  proper  time 
for  making  the  exposure.  The  sunlight  falls  upon  the  object  at  dif- 
ferent angles  and  in  different  directions  at  different  hours  of  the  day. 
Whether  the  ol)jcct  is  photographed  in  the  early  morning,  in  the 
late  morning,  at  noon,  or  in  the  afternoon  is  usually  within  the  con- 
trol of  the  photographer,  and  it  makes  a  difference  in  the  pictorial 
value  of  the  photograph.  Few  landscapes  are  pretty  at  noon,  with 
the  shadow  exactly  under  each  tree  and  bush;  they  are  far  better 
between  two  o'clock  and  five  o'clock  in  the  afternoon.  The  horizontal 
rays  of  sunlight  become  objectionable  again  in  the  late  afternoon. 
The  second  method  of  control  for  immovable  objects  is  the  selec- 
tion of  an  overcast  or  hazy  day  in  preference  to  a  day  of  direct  sun- 
light. Usually  the  direct  sunlight,  with  sharp  shadows  is  preferable, 
but  here  again  the  operator  has  control  of  the  image  in  his  hands. 

Size  of  Object.    The  size  of  the  princi])al  object  is  controlled  by 


30 


PHOTOGRAPHY  21 

the  distance  from  the  camera  to  the  object  and  by  the  focal  length 
of  the  lens.  The  nearer  the  camera  is  carried  to  the  object  to  be  pho- 
tographed, the  larger  will  be  the  image  of  that  object  upon  the  ground 
glass.  The  longer  the  focal  length  of  the  lens  used,  the  larger  will 
be  the  image  upon  the  ground  glass.  The  image  of  the  main  object, 
therefore,  may  be  enlarged  by  using  one  of  the  lenses  alone  instead 
of  both  of  them  double. 

Composition  and  Balance.  By  the  terms  composition  and  balance 
reference  is  made  to  the  many  relations  which  exist  among  the  masses 
of  light  and  shade  among  the  lines  of  the  image.  The  rules  are 
so  numerous  that  all  of  them  cannot  be  followed  at  all  times,  and 
many  of  them  apply  only  to  specific  instances  of  subject  arrange- 
ment. A  few  of  the  more  general  rules  may  be  kept  in  mind  when 
arranging  the  image  upon  the  ground  glass. 

A  profile  portrait  shows  on  one  side  the  light  face  against  the 
darker  portion  of  the  background,  and  on  the  other  side  the  dark 
hair  against  .the  lighter  portion  of  the  background.  Each  side  of 
the  picture  has  its  lights  and  its  shadows.  A  landscape,  even  the 
picture  of  a  building,  should  bear  the  same  analysis.  A  balanced 
picture  should  have  a  principal  shadow,  and  some  minor  shadows. 
It  should  have  a  principal  high  light  and  some  minor  high  lights. 
With  the  principal  shadow  and  the  minor  high  lights  on  one  side  of 
the  image  and  the  principal  high  light  and  minor  shadows  on  the 
other  side,  it  is  likely  that  an  approximate  balance  will  be  obtained. 
For  example:  a  heavy  mass  of  foliage  is  at  the  lower  right,  as  a  near 
bush  or  tree:  a  few  scattered  masses  are  at  the  middle  left  and  upper 
left,  as  distant  bushes  or  trees;  a  roadway  or  stream  runs  from  lower 
left  to  upper  right,  showing  a  large  light  spot  at  lower  left  and  smaller 
light  spots  at  upper  right;  the  large  light  is  a  little  higher  or  a  little 
lower  than  the  large  shadow,  not  dead  level  that  a  line  connecting 
them  would  be  parallel  to  the  margin.  That  sounds  like  a  coldly 
critical  analysis  suitable  for  producing  a  stiff  and  formal  picture,  yet 
a  scene  sought  out  in  nature  and  photographed  from  a  viewpoint  care- 
fully selected  to  secure  this  arrangement  of  lights  and  shadows  will 
rank  above  a  hand-camera  snapshot  and  will  repay  the  amateur's  effort. 

In  a  water  scene,  a  ship  at  anchor  may  be  photographed  from 
the  pier  with  another  pier  in  the  background.  Place  the  dark  hull 
of  the  ship  near  the  lower  edge  of  the  picture  and  at  the  right  of  the 


SI 


22  THE  MOTION  PICTURE 

middle  line;  place  the  distant  pier  above  the  center  on  the  left  of  the 
picture.  The  masts  of  the  ship  cut  up  into  the  upper  right  corner 
and  break  up  the  sea  and  sky  into  minor  high  lights.  The  major 
high  light  is  the  unbroken  sea  at  the  left  of  the  ship,  lower  left  corner 
of  the  picture. 

Strictly  parallel  lines  are  objectionable  in  a  picture  unless  they 
are  parts  of  an  object  and  unavoidable,  as  the  masts  of  a  ship.  Any 
line  parallel  to  the  margin  of  the  plate  is  objectionable  except  the 
side  lines  of  buildings,  which  are  unavoidable.  An  imaginary  line 
joining  two  high  lights  or  two  shadows  should  not  be  parallel  to 
an  edge  of  the  plate,  nor  should  an  imaginary  line  from  the  principal 
shadow  mass  to  the  principal  high  light  be  parallel  to  any  edge  of  the 
plate  if  it  can  be  avoided.   The  horizon  Une  requires  care  in  this  detail. 

Horizon  Line.  The  placing  of  the  horizon  line  has  much  in- 
fluence in  the  composition  and  balance  of  the  picture.  Care  must 
be  taken  that  the  horizon  line  does  not  cross  the  principal  object 
at  an  undesirable  point,  nor  should  the  apparent  horizon  divide 
the  picture  exactly  in  the  middle.  Where  a  hillside  is  included  in 
the  landscape,  it  may  be  made  to  give  an  inclined  or  irregular  line 
for  the  horizon.  Where  a  level  horizon  is  unavoidable,  it  should  be 
broken  if  possible  by  the  objects  of  the  picture. 

Point  of  View.  The  point  of  view  is  the  location  of  the  camera 
whence  the  image  is  made.  Changing  the  point  of  view  is  the  most 
powerful  means  which  the  camera  operator  has  for  arranging  and 
controlling  his  image.  The  selection  of  the  background  depends 
almost  solely  upon  the  point  of  view  chosen.  The  size  of  the  prin- 
cipal object  is  largely  controlled  by  the  choice  of  the  point  of  view, 
while  the  composition  and  balance  are  almost  wholly  controlled  by 
the  selection  of  the  point  of  view,  together  with  the  selection  of  the 
lens  length. 

Prominence  of  Background.  As  a  rule,  the  image  may  be 
separated  into  principal  object  and  background,  even  though  the 
background  or  setting  of  the  principal  object  be  really  the  more 
important  portion  of  the  picture,  and  the  portion  primarily  desired. 
The  relative  size  of  the  principal  object  and  its  associated  background 
objects  may  be  controlled  by  the  lens  length.  With  the  double 
lens,  focus  upon  a  view  containing  a  near  tree  as  a  principal  object. 
Note  the  size  of  the  distant  trees.    Remove  the  front  lens  cell,  move 


32 


PHOTOGRAPHY 


23 


the  camera  back  to  twice  the  distance  from  the  principal  tree,  and 
focus  again.  By  the  change  of  the  lens  and  the  change  of  the  point 
of  view,  the  principal  tree  will  be  the  same  size  as  before;  note  that 
the  distant  trees  are  much  larger  than  before,  thus  giving  greater 
prominence  to  the  objects  of  the  background.  Also,  by  the  use 
of  the  longer  focus  of  the  single  lens,  less  of  the  horizon  is  included 
in  the  image,  and  less  of  the  surrounding  landscape  is  shown  as  a 
background  to  the  principal  tree,  that  which  is  included  in  the  image 
being  shown  in  larger  size.    If  the  front  and  back  cells  of  the  lens 


Fig.  23.    Perspective  Distortion 

are  different  in  length,  the  front  cell  alone  will  give  still  more  prom- 
inence to  the  background  objects,  a  greater  extension  of  bellows  and 
a  still  more  distant  viewpoint  being  required  to  keep  the  principal 
object  at  the  original  chosen  size.  When  it  is  impossible  to  secure 
a  point  of  view  near  enough  to  the  principal  object  to  secure  a  large 
image,  the  longest  lens  will  give  the  largest  possible  image. 

In  the  case  of  a  portrait,  the  background  is  entirely  unimportant 
in  detail,  and  is  most  satisfactory  when  shown  merely  as  a  blurred 
surface  of  light  and  shade.  This  is  effected  by  opening  the  diaphragm 
to  its  largest  stop  size,  then  bringing  theJace  of  the  portrait  to  a  sharp 


33 


24  THF  MOTION  PICTURE 

ocus.  The  -background  will  be  blurred  because  it  is  "out  of  focus." 
Out-of-door  portraiture  profits  by  the  same  rule,  and  the  rule  applies 
generally  where  the  picture  is  to  be  a  photograph  of  a  specific  object 
and  the  background  is  not  a  part  of  the  object.  ^Yhere  both  fore- 
ground and  background  are  required  to  be  sharp,  a  small  stop 
opening  must  be  used  to  secure  the  result. 

Distortions.  Usually,  any  distortion  of  the  image  caused  by 
the  lens  is  objectionable.  Blurring  the  background  in  portraiture 
and  similar  pictures  by  using  the  shallow  field  incidental  to  the  large 
stop  opening  is  in  itself  a  form  of  distortion  which  is  made  to  serve 
a  useful  purpose  and  is  an  aid  to  the  operator  in  the  control  of  his 
image. 

Barrel  distortion  and  pin-cushion  distortion,  which  have  already 
been  discussed,  should  be  avoided  as  far  as  possible,  particularly  in 
architectural  subjects. 

Perspective  distortion  will  be  observed  if  the  camera  does  not 
stand  level  upon  its  tripod.      In  landscape  \dews,  such  distortion 


FipT.  21.    Camera  '"Mi  SAing  Back  Fig.  25.    Camera  with  Rising  Front 

in  Use  in  Use 

usually  is  negligible.  In  architecture  it  is  ludicrous,  Fig.  23.  The 
remedy  is  to  keep  the  ground  glass  vertical,  or  nearly  so.  This  is 
done  by  the  swing  back  and  by  the  rising  front. 

Swing  Back.  When  the  back  of  the  camera,  carrying  the  ground 
glass  and  the  plate-holder,  is  pivoted  or  hinged,  the  body  of  the  camera 
may  be  tilted  to  bring  the  desired  scene  upon  the  ground  glass, 
and  the  swinging  back  of  the  camera  then  may  be  adjusted  to  bring 
the  ground  glass  vertical  or  nearly  so.  Fig.  24.  By  this  adjustment, 
the  perspective  distortion  will  be  corrected,  but  the  focus  is  more 


34 


PHOTOGRAPHY  25 

difficult  and  a  smaller  stop  opening  will  be  required  to  give  a  sharp 
focus  over  the  entire  plate. 

Rising  Front.  With  the  camera  placed  about  level,  more  of 
the  sky  or  more  of  the  foreground  may  be  included  upon  the  plate 
by  raising  or  lowering  the  lens  in  the  front  of  the  camera,  Fig.  25. 
This  avoids  perspective  distortion,  but  the  amount  of  adjustment 
thus  obtainable  is  somewhat  limited. 

RECORDING  THE  IMAGE 

The  recording  of  the  image  consists  of  two  processes — expos- 
ing the  sensitive  plate  and  developing  the  exposed  plate  into  a  negative. 

Dry  Plates.  The  art  of  the  chemist  is  brought  into  use  in  record- 
ing the  image  of  the  lens.  The  known  substance  most  sensitive  to 
light  is  finely  divided  nitrate  of  silver  suspended  in  gelatine.  The 
manufacture  of  this  substance  is  not  attempted  by  the  photographer. 
A  thin  skin  of  the  prepared  gelatine  is  spread  upon  glass  plates 
and  dried.  The  plates  thus  made  are  sold  under  the  name  of  photo- 
graphic dry  plates.  These  are  bought  by  the  photographer  in  light- 
proof  sealed  packages  and  loaded  into  plate-holders  in  the  darkroom. 

Films.  Flexible  transparent  celluloid  films  coated  with  the 
prepared  gelatine  are  used  instead  of  the  glass,  if  desired,  and  may 
be  had  for  pictures  up  to  a  5  by  7  size,  either  in  packets  of  cut  films 
or  in  rolls  of  proper  width  on  which  exposures  may  be  made  one  after 
another.  In  motion-picture  work,  the  celluloid  film  is  a  necessity 
and  it  is  used  universally  in  commercial  motography. 

Exposure.  \Yhen  the  plate-holder  is  inserted  in  the  camera, 
the  lens  closed,  and  the  dark  slide  withdrawn,  the  lens  is  opened 
just  long  enough  to  permit  a  sufficient  amount  of  light  to  pass  through 
the  lens  to  affect  the  sensitive  silver  of  the  dry  plate — neither  too 
much,  nor  too  little.  This  process  of  administering  to  the  plate 
the  proper  dose  of  light  in  the  form  of  the  image  is  called  exposing 
the  flaie. 

The  greatest  problem  in  photographing  any  subject  is  the  best 
arrangement  of  the  image  upon  the  ground  glass,  and  the  next 
greatest  is  the  determination  of  how  long  a  time,  in  seconds  or  frac- 
tions of  a  second,  to  permit  the  light  to  flow  through  the  lens  to 
impress  the  image  properly  upon  the  sensitive  plate. 

The  amount  of  light  from  a  given  subject  which  falls  upon 


35 


26  THE  MOTION  PICTURE 

the  sensitive  plate  to  impress  the  image  depends  upon  the  size  of 
the  stop  opening  and  the  length  of  time  during  which  the  lens  is 
left  open  for  the  exposure.  Light  flowing  through  the  stop  opening 
is  just  like  water  flowing  through  a  hole.  If  you  increase  the  size 
of  the  hole,  the  bucket  will  be  filled  with  water  in  less  time,  and  in 
direct  proportion  to  the  change  of  the  size  of  the  hole.  Double-size 
hole,  half  the  time  to  fill  the  bucket.  Half-size  hole,  double  time  to  fill 
the  bucket.  A  hole  ten  times  the  size  will  fill  the  bucket  in  one-tenth 
the  time.  This  rule  holds  strictly  true  in  the  case  of  the  photographic 
exposure.  Increase  the  size  of  the  stop  opening  and  the  light  passes 
through  faster,  giving  the  plate  sufficient  light  in  a  shorter  time. 

A  larger  plate  requires  a  greater  quantity  of  light  because  there 
is  more  surface  to  be  worked  upon,  The  Hght  spreads  from  the 
lens,  and  the  farther  back  from  the  lens  the  light  must  go  to  reach 
the  plate,  the  more  it  spreads  out  and  the  weaker  it  becomes.  The 
lens  length  has  a  direct  influence  in  the  strength  of  light  upon  a  plate 
from  a  given  subject  through  a  given  opening  or,  to  state  the  same 
rule  differently,  the  lens  length  has  a  direct  influence  in  determining 
the  size  of  stop  opening  which  mv^t  be  used  to  effect  the  same  strength 
of  light  upon  a  plate  from  a  given  subject. 

Stop  Numbers.  A  plan  of  numbering  stops  according  to  the 
size  of  the  opening  has  been  devised  which  removes  the  actual  focal 
length  of  the  lens  from  the  calculation  of  the  strength  of  the  light 
upon  the  plate,  by  including  the  focal  length  of  the  lens  in  the  deter- 
mination of  the  stop  number.  There  are  in  common  use  in  America 
two  systems  of  stop  numbers — the  focal-factor  system  and  a  modifi- 
cation called  the  uniform  system.  The  plan  used  in  the  focal  factor 
system  consists  of  numbering  the  stops  in  fractions,  as  1/8,  1/16, 
1/32  of  the  focal  length  of  the  lens;  these  are  written //8,  //16,  //32, 
etc.,  or  F/8,  F/16,  F/32,  etc.,  or  /-8,  /-16,  /-32,  etc.,  or  /:8,  /:16, 
/:32,etc. 

The  stop  number  //16  means  that  the  diameter  of  the  stop 
opening  is  1/16  the  focal  length  of  the  lens.  An  //16  stop  for  a 
4-inch  lens  is  1/4  inch  in  diameter.  An  //16  stop  for  an  8-inch  lens 
is  1/2  inch  in  diameter,  giving  four  times  the  area  of  the  stop  open- 
ing, giving  four  times  the  quantity  of  light,  but  since  the  light  goes 
twice  as  far  before  it  reaches  the  ground  glass  or  sensitive  plate  it 
will  spread  over  four  times  the  area  and,  therefore,  will  be  of  the 


36 


PHOTOGRAPHY 


27 


same  strength,  or  intensity,  on  the  plate  with  the  1/2-inch  stop  //16 
of  the  8-inch  lens  as  with  the  1/4-inch  stop  //16  of  the  4-inch  lens. 
This  is  of  great  convenience  in  writing  of  exposure  timing,  because 
by  the  use  of  the  focal-factor  system  of  stops  all  the  rules  given  for 
exposure  will  be  true  for  cameras  of  all  sizes  and  for  lenses  of  all 
lengths  of  focus. 

In  both  systems  each  stop  number  requires  either  double  or 
half  the  exposure  of  the  next  stop  number,  the  stops  being  alike  at 
//16  and  No.  16.  If  the  stop  numbers  on  a  scale  are  4,  8,  16,  32,  64, 
128,  256,  it  is  "U.  S."  or  uniform  system.  If  the  stop  numbers  on 
a  scale  are  8,  11,  16,  22,  32,  45,  64,  it  is  focal-factor  system.  In 
either  case,  as  the  numbers  increase  each  number  requires  double 
the  time  of  exposure  required  for  the  preceding  or  next  smaller 
number.  In  any  lens,  the  largest  opening  possible  may  not  be  an 
even  stop  number,  and  this  first  marking  of  the  scale  may  vary  from 
the  "double  time"  rule.  Thus,  if  a  lens  will  work  with  an  opening 
of  //7,  its  scale  will  be  marked  7,  8,  11,  16,  etc.,  if  for  the  focal- 
factor  system;  or  3,  4,  8,  16,  etc.,  if  for  the  "U.  S."  system.  In  Table 
I  the  numbers  in  the  two  systems  are  compared. 

TABLE  I 
Equivalent  Stop  Numbers  in  Focal-Factor  and  Uniform  Systems 


f/2 

f/3.5 

f/4 

f/4.5 

f/5 

f/o.6 

f/6.3 

f/7 

No.  i 

No.  1 

No.  1 

No.  U 

No.  U 

No.  2 

No.  2i 

No.  3 

*f/S 

*f/ll 

*f/16 

*f/22 

*f/32 

*f/45 

f/64 

f/90 
No.  512 

No.  4 

'"No.  8 

No.  16 

No.  32 

No.  64 

No.  128 

No.  256 

*The  stop  numbers  in  the  two  systems  which  are  most  commonly  met  and  used. 

Plate  Speed.  Some  plates  are  coated  with  a  gelatine  film  which 
is  more  sensitive  to  light  than  others.  As  a  standard,  plates  such  as 
Seeds  26x,  Stanley,  Hammer  Fast,  Cramer  Instantaneous  Iso,  and 
Standard  Extra  may  be  taken  as  most  suitable  in  speed  for  amateur 
work.  These  plates  list  130  on  the  Watkins  scale  of  plate  speeds. 
A  faster  class  of  plates  comprises  Cramer  Crown,  Hammer  Extra 
Fast,  Seed  27,  and  Kodak  and  Premo  Films.  These  list  at  180  on 
the  Watkins  scale  and  require  only  three-quarters  the  exposure  to 
impress  the  image  as  fully  as  upon  a  plate  of  the  130  class. 


37 


28  THE  MOTION  PICTURE 

Light  Intensity.  In  filling  a  bucket  with  water  running  through 
an  opening,  the  pressure  which  is  behind  the  water  will  influence 
the  rate  of  flow  and  will  influence  the  time  required  to  fill  the  bucket. 
The  intensity  of  the  light  which  illuminates  the  subject  and  the 
nature  of  the  subject  itself  are  the  two  elements  which  influence  the 
rate  of  flow  of  light  through  the  lens  opening.  On  a  dark  day  the 
light  does  not  pour  through  the  small  stop  opening  as  fast  as  on  a 
day  of  Winding  sunlight.  Even  in  the  same  bright  sunlight,  the 
quantity  of  light  sent  to  the  camera  from  a  dark  green  tree  is  less 
than  the  quantity  sent  from  the  white  sails  of  a  ship.  One  considera- 
tion of  the  nature  of  the  subject  also  is  its  distance  from  the  camera. 

If  the  average  amateur  photographer  were  asked  the  exposure 
for  a  summer  landscape,  he  would  probably  say,  carelessly,  //1 6 
and  1/25  of  a  second.  That  is  the  hand-camera  way  and  gives  but 
twenty  good  negatives  out  of  a  thousand  exposures. 

The  intensity  of  light  depends  upon  the  height  of  the  sun  above 
the  horizon,  which  varies  with  every  day  of  the  year  and  with  every 
hour  of  the  day.  With  a  clear  sky  and  an  average  subject.  Table 
II  gives  in  seconds  the  proper  exposure  (Watkins  130  list  plate) 
for  //16  stop  for  each  hour  of  the  year,  by  months,  for  the  latitude 
of  the  northern  portion  of  the  United  States. 

In  the  southern  portion  of  the  United  States,  three-quarters 
of  this  exposure  is  sufficient;  and  on  the  equator,  probably  one- 
half  is  sufficient,  and  the  May-June-July  column  may  be  used  all 
the  year  around,  with  the  5  a.  m.  and  7  p.  m.  figures  omitted. 

For  a  hazy  day — good  daylight  but  cloudy  enough  to  obscure 
the  sun — give  double  the  exposure  as  a  correction  for  the  clouds. 
On  a  heavily  overcast,  gloomy  day,  give  four  times  the  exposure  as 
a  correction  for  clouds. 

Nature  of  Subject.  The  nature  of  the  subject  to  be  photographed 
has  an  influence  even  greater  than  the  time  of  day  or  condition  of 
the  clouds.  For  pictures  in  the  middle  of  the  day,  a  glance  at  the 
table  shows  that  the  midwinter  exposure  with  sun  is  but  little  more 
than  double  the  midsummer  exposure  with  sun.  The  exposure  for 
cloudy  days  is  only  twice  or  four  times  that  for  sunny  days.  But 
the  correction  for  the  nature  of  the  subject  even  with  outdoor  subjects 
may  be  two  hundred  times  as  much  for  one  subject  as  for  another. 

The  following  corrections  may  be  applied  to  Table  II  to  com- 


88 


PHOTOGRAPHY 


29 


TABLE  II 
Day  and  Hour  Exposure  Chart 


A.    M. 
P.    M. 

Jan. 

Feb. 

Mar. 

Apr. 

May 
June 
July 

Aug. 

Sep. 

Oct. 

Nov. 

Dec. 

5  A.M. 

1 

6  A.M. 

1 

1/2 

1/5 

1/2 

1 

7  A.M. 

8  A.M. 

2 

1/2 

1/5 

1/10 

1/10 

1/10 

1/5 

1/2 

2 

2 

1/2 

1/5 

1/10 

1/10 

1/10 

1/10 

1/10 

1/5 

1/2 

1/2 

9  A.M. 
10  A.M. 

to 

2   P.M. 

1/5 

1/10 

1/10 

1/15 

1/15 

1/15 

1/10 

1/10 

1/5 

1/5 

1/10 

1/5 

1/15 

1/15 

1/25 

1/25 

1/25 

1/15 

1/15 

1/10 

1/10 

3    P.M. 

1/10 

1/10 

1/15 

1/25 

1/25 

1/15 

1/10 

1/5 

1/5 

4    P.M. 

1/2 

1/5 

1/10 

1/10 

1/15 

1/15 

1/10 

1/5 

1/2 

1/2 

5   P.M. 

2 

1/2 

1/5 

1/10 

1/10 

1/10 

1/5 

1/2 

2 

2 

6   P.M. 

1 

1/2 

1/5 

1/2 

1 

7  PM. 

1             1 

1 

pensate  for  the  difference  in  the  character  of  the  subject  of  different 
images. 

1/20  exposure  for  sky  and  clouds,  where  the  foreground  objects  do  not 
form  a  part  of  the  picture. 

1/10  exposure  for  sea  and  sky,  ships  at  a  distance  at  sea,  views  at  a 
distance  across  the  water. 

1/4  exposure  for  open  views,  where  the  important  portion  of  the  view 
is  in  the  distance  and  the  foreground  is  unimportant. 

1/2  exposure  for  very  light  objects  of  importance  in  the  foreground. 

Exposure  time  given  in  the  table  is  suitable  when  the  important  objects 
of  the  image  are  20  to  100  feet  from  the  camera  and  are  neither  white  nor 
black,  neither  very  light  nor  very  dark. 

Twice  the  exposure  time  given  in  the  table  for  objects  nearer  than  20 
feet,  or  for  dark  objects  of  importance  in  the  foreground  of  the  image. 

Four  times  the  exposure  time  for  portraits  in  shade  of  heavy  foliage, 
and  for  dark  objects  nearer  than  20  feet. 

Sixteen  times  the  exposure  time  for  pictures  in  dense  woods  where  side 
light  as  well  as  top  light  is  obstructed  by  the  foliage  of  the  trees. 

Near  sunset,  five  times  the  exposure  in  order  to  compensate  for  the 
yellow  color  of  the  sunset  light. 

Interiors,  if  very  well  lighted  by  windows  and  with  light  walls,  100  times 
the  table  values. 

Interiors,  if  not  well  lighted,  500  to  5,000  times. 

When  the  sun  is  in  front  of  the  camera  so  that  the  shady  side  of  the 
subject  is  being  photographed,  the  exposure  should  be  doubled. 


39 


30 


THE  MOTION  PICTURE 


Calculation  of  Exposure  by  Table.  To  calculate  an  exposure 
requires  that  the  proper  //16  time  for  average  plate  and  subject  be 
taken  from  Table  II.  If  the  subject  is  an  average  one  and  the  sum- 
mer day  is  bright,  then  there  is  no  correction  to  be  appUed,  the  stop 
is  set  to  //1 6,  and  the  figure  taken  from  the  table  is  set  upon  the 
automatic  shutter  and  the  exposure  is  made.  A  few  exceptions  may 
be  studied. 

The  summer  hotel  presents  from  across  the  valley  a  view  which 
the  visitor  wishes  to  take  with  him.  At  one  point  in  the  road  a  group 
of  trees  between  the  road  and  the  hotel  obscures  the  hotel,  but  by 
taking  a  viewpoint  farther  along  the  hotel  is  free  from  the  ob- 
struction  and   the  group  of   trees  at  one  side  of  the  middle  of  the 

image  balances  the  hotel  at  the  other 
side.  The  trees  being  nearer  and  larger 
are  the  "main  object"  of  the  com- 
position, but  the  building  is  the  more 
important.  It  is  painted  white.  Trees 
behind  it  show  its  outline  definitely, 
and  both  the  trees  behind  and  the 
"main  object"  group  of  nearer  trees 
break  the  horizon  line.  The  horizon 
line  is  placed  high — three-fifths  from 
the  bottom  and  two-fifths  from  the  top 
line  of  the  picture.  If  possible,  the  cam- 
era is  so  positioned  by  its  selection  of 
viewpoint  that  some  small  object  breaks 
the  foreground  on  the  side  opposite  the 
"main  object"  group  of  trees.  The  ex- 
posure is:  Summer,  2  p.  m.,  by  Table  II,  1/25  second;  important 
portion  of  the  view  is  in  the  distance  and  foreground  unimportant, 
correction  1/4;  the  exposure  should  be  1/100  second  at  //16,  but 
better  1/25  second  at  //32  to  increase  the  sharpness  of  the  distant 
object.  ///  a  light  subject,  give  less  rather  than  more  time  than  given 
in  the  table. 

Further  along,  the  visitor  passes  through  a  wood  and  notes  a 
clump  of  pretty  ferns.  The  table  says  1/25  second;  correction  for 
deep  wood,  16;  correction  for  dark  color  (green)  of  ferns,  and  near 
the  camera,  to  have  the  image  of  the  ferns  large,  4.    Time  04/25  or 


Fig.  26. 


Watkins  Exposure 
Meter 


40 


PHOTOGRAPHY 


31 


2^  seconds  at  //16.     In  a  dark  subject,  give  too  much  rather   than 
too  little  time  by  the  table. 

Exposure  Meters.  The  exposure  meter  is  a  device  for  measur- 
ing the  strength  of  the  light  which  falls  upon  the  subject.  It  takes 
the  place  of  Table  II  and  of  the  correction  for  the  clouds.  Two 
types  of  exposure  meters  in  general  use  are  the  Watkins,  Fig.  26, 
and  the  Wynne,  Fig.  27. 

The  principle  of  both  meters  is  the  same.  A  disk  of  paper 
which  is  discolored  rapidly  by  light  is  movable  behind  a  slot,  and 
beside  the  slot  are  bits  of  color  which  the  paper  matches  in  the  course 
of  its  discoloration  under  the  influence  of  light.  The  more  intense 
the  light,  the  more  rapidly  does  the  exposed  bit  of  the  paper  disk 
become  discolored,  and  the  sooner  does  it  reach  a  tint  which 
matches  one  of  the  bits  of  color  adja- 
cent to  the  slot.  The  time  required  to 
match  the  darker  color  is  taken  as  ac- 
tinic value  of  the  light.  An  exposure- 
calculating  disk  forms  a  part  of  each 
meter.  Upon  and  near  the  calculating 
disk  are  sets  of  figures  for  (a)  the  ac- 
tinic or  meter  value  of  the  light,  as  noted 
in  the  number  of  seconds  which  is  taken 
by  the  paper  to  discolor  to  match  the 
dark  standard  tint;  (b)  the  speed  of  the 
plate  which  is  to  be  used  in  the  ex- 
posure; (c)  the  diaphragm  stop;  and  (d) 
the  required  exposure  in  seconds  or 
fraction  of  a  second. 

The  difference  between  the  two  meters  is  found  in  the  cal- 
culating device.  In  the  Watkins,  the  stop  number  is  set  opposite 
the  plate  number;  then  opposite  the  time  required  for  the  paper  to 
darken  is  found  the  time  required  to  impress  the  image  upon  the 
plate,  that  is,  the  exposure  time,  to  which  the  correction  for  the 
nature  of  the  subject  must  be  applied.  This  appears  to  be  the  more 
convenient  meter  for  the  amateur  either  with  hand  camera  or  tripod. 
In  the  Wynne,  the  time  required  by  the  paper  to  darken  is  set  opposite 
the  speed  number  of  the  plate;  then  opposite  the  stop  number  is 
read  the  required  exposure  for  a  standard  subject,  to  which  the  cor- 


Fig.   2t. 


Wynne  Exposure 
Meter 


41 


32  THE  MOTION  PICTURE 

rection  for  the  nature  of  the  subject  must  be  appHed.  This  is  the 
more  convenient  for  the  motion-picture  camera  operator  because 
of  an  exposure  Hmitation  in  the  motion-picture  art.  The  Wynne 
meter  is  preferred  by  many  fixed  camera  operators  who  have  be- 
come familiar  with  it.  Full  instructions  for  use  accompany  either 
meter  when  purchased. 

There  are  also  upon  the  market  many  exposure  meters,  so- 
called,  which  are  but  calculating  devices  for  combining  the  date 
table  with  the  cloud  correction,  subject  correction,  stop  number, 
and  plate  speed.  Perhaps,  when  facility  has  been  acquired  with 
one  of  them,  it  would  be  found  convenient. 

Exposures  with  Single  Lens,  ^^^len  the  front  lens  of  a  double 
lens  is  removed,  for  the  purpose  of  obtaining  a  larger  image,  or 
to  increase  the  prominence  of  the  background,  the  focal  length  of 
the  lens  has  been  changed,  without  changing  the  marldngs  of  the 
diaphragm  scale;  these  markings,  therefore,  are  not  correct  for  the 
sinde  lens.  To  obviate  this,  some  lenses  have  two  or  three  sets  of 
markings  on  the  diaphragm  scale,  one  for  the  double  lens  and  one 
for  a  single  lens  if  both  singles  be  of  the  same  focal  length,  while 
if  the  singles  be  of  different  focal  lengths  there  may  be  three  mark- 
ings,  one  for  the  double  lens  and  one  for  each  of  the  singles. 

Where  the  singles  are  of  the  same  focal  length,  the  exposure 
time  for  a  single  lens  will  be  four  times  that  for  the  double  lens  with 
the  same  stop  setting,  to  compensate  for  the  difference  in  focal  length 
between  double  and  single. 

Wliere  the  singles  are  of  different  focal  lengths,  the  exposure 
for  the  short  single  will  be  three  times  that  for  the  double  lens,  and 
the  exposure  for  the  longer  single  will  be  six  times  that  for  the  double 
lens. 

Duplicate  Exposures,  ^^^len  much  is  in  doubt,  and  upon  sub- 
jects which  cannot  be  photographed  again,  two  exposures  may  be 
made,  using  two  plates,  and  giving  different  lengths  of  exposure. 
If  the  range  of  exposure  is  such  that  one  plate  has  ten  times  the 
exposure  of  the  other  both  may  give  good  negatives,  whereas,  if 
this  ratio  is  increased  to  twenty-to-one,  disappointment  may  be 
met  by  finding  one  plate  under-exposed  and  the  other  over-exposed. 
As  an  over-exposure  is  a  better  printing  proposition  than  an  under 
exposure,  a  good  rule  for  duplicate  exposures  is  as  follows: 


42 


o 

H 

» 
O 

«  s  ^ 

H    o 
(«  -5  & 
t) 
O 


^'^^ 


«    a,  e 

M  J  n, 

H  *^  S 

Z 
& 

c 

tii 

K 

O  j^A 


oar 


^S; 


o  >i 


O    g  o 

o 

<! 


PHOTOGRAPHY  33 

Estimate  the  exposure,  then  give  one  plate  half  the  estimate  and 
the  other  plate  five  times  the  estimate.  '■ 

Development.  The  subject  having  been  selected  and  arraned 
upon  the  ground  glass,  and  the  sensitive  plate  having  been  inserted 
and  exposed  by  setting  the  diaphragm  as  determined  by  judgment 
of  the  image,  and  setting  and  releasing  the  shutter  as  determined 
by  meter  or  Table  H  and  judgment  of  the  nature  of  the  subject, 
the  field  work  for  that  particular  plate  is  finished.  Other  plates 
may  be  exposed  before  developing  the  first,  and  development  may 
be  done  either  immediately  after  exposure  or  after  a  lapse  of  a  few 
days  or  weeks. 

The  exposed  plate  is  still  sensitive  to  light  and  must  be  kept 
in  the  holder  with  the  slide  closed  until  removed  in  the  darkroom. 
As  the  plate  itself  bears  no  evidence  whatever  of  ha\dng  been  ex- 
posed, it  is  impossible  to  tell  an  exposed  plate  from  an  unexposed 
one  except  by  applying  a  dereloper,  which  brings  out  the  image  if 
exposed  and  spoils  the  plate  if  unexposed.  The  indication  in  the 
field  or  in  the  darkroom  that  a  plate  has  been  exposed  is  the  sUde 
of  the  holder,  which  should  have  its  white  side  out  for  an  unexposed 
plate  and  its  black  side  out  for  an  exposed  plate.  The  plate  when 
exposed  is  said  to  contain  a  latent  image,  because  the  invisible  image 
may  be  brought  out  and  made  visible  by  a  process  called  develop- 
ment. This  is  done  by  soaking  the  plate  in  a  chemical  solution 
which  turns  the  nitrate  of  silver  black  only  where  it  has  been  struck 
by  the  light  but  does  not  affect  it  otherwise. 

Negative  Image.  The  gelatine  film  of  the  plate  when  developed 
shovv-s  the  image  which  was  seen  upon  the  ground  glass,  but  with 
its  lights  and  shadows  reversed.  A  black  sky  is  seen  above  a  white 
grassy  foreground;  a  black  brook  flows  under  white  trees;  the  figures 
in  the  picture  are  black  of  face  and  have  white  hair. 

Developers.  There  are  many  different  developers  on  the  market, 
each  with  its  claims.  The  selection  is  a  matter  of  personal  opinion, 
and  in  the  writer's  opinion  there  is  no  developer  as  good  as  pyro 
and  soda,  although  it  stains  the  fingers  if  the  operator  is  careless 
about  slopping  around  in  the  darkroom.  Hydroquinone  and  metol 
developer  is  second  choice,  and  this  does  not  stain  the  fingers. 

For  the  first  few  plates  to  be  developed,  the  amateur  should 
buy  a  ready-mixed  developer,  either  liquid  or  powder  form,  to  avoid 


43 


34  THE  MOTION  PICTURE 

the  possibility  of  losing  all  of  the  first  batch  of  plates  through  an 
error  in  compounding  the  developing  solutions,  and  to  avoid  plac- 
ing a  blame  upon  improper  exposure  when  the  actual  fault  is  an 
error  in  compounding  the  developer.  Formulas  for  developers  will 
be  given  after  the  processes  of  development  with  ready-mixed  de- 
velopers have  been  studied. 

Trays  and  Covers.  The  developing  tray  is  a  flat  dish  having 
a  flat  bottom  so  the  glass  plate  will  lie  close  upon  the  bottom  of  the 
tray.  Half  a  dozen  should  be  available,  each  the  proper  size  for 
one  plates.  Covers  for  the  trays  should  be  light  tight.  A  good  cover 
is  a  developing  tray  of  such  size  that,  when  turned  over  the  smaller 
developing  tray,  it  will  come  down  to  the  developing  table  or  shelf 
all  around  the  edge.  Almost  as  good  but  not  so  convenient  a  cover 
is  a  folded  paper  larger  than  a  tray  laid  across  the  top  of  the  tray 
and  a  flat  weight,  such  as  a  small  piece  of  wood  larger  than  the 
developing  tray, which  is  laid  upon  the  paper  and  holds  it  close  to 
the  top  of  the  tray  all  around  the  edge.  A  measuring  glass  and  a 
thermometer  will  be  needed. 

Ruby  Lamp.  A  "safe"  light  is  one  which  may  shine  upon  a 
sensitive  plate  without  spoiling  the  plate.  Such  a  light  is  a  theoretical 
proposition.  I  To  determine  whether  your  ruby  lamp  is  safe,  cover 
half  a  plate  and  expose  for  five  minutes  to  the  direct  rays  of  the 
lamp  two  feet  away.  Then  develop.  If  the  half  exposed  to  the 
light  is  fogged,  the  lamp  is  not  entirely  safe,  although  it  may  be  good 
enough.  Very  few  lights  are  safe  which  are  strong  enough  to  be  of 
any  use.  It  is  quite  possible  to  use  an  unsafe  lamp  without  spoil- 
ing plates;  that  is  the  object  of  the  tray  covers.  The  writer  has  de- 
veloped many  plates  and  films  when  he  did  not  have  a  red  lamp  at  all. 

Sight  Development.  In  preparation  for  development,  set  a 
tray  18  inches  or  2  feet  from  the  red  lamp.  Beside  it  place  the  meas- 
uring glass  or  a  drinking  glass  containing  four  ounces — for  4  by  5 — 
or  six  ounces — for  5  by  7 — of  developer  at  Go  degrees  by  the  ther- 
mometer, ready  to  pour  upon  the  plate  to  be  developed.  Have  a 
cover  for  the  developing  tray  handy.  A  foot  or  more  away,  beyond 
the  reach  of  splashes,  place  the  plate-holder  containing  the  exposed 
plate  to  be  developed.  A  pan  of  water,  larger  than  the  plate,  is 
convenient  for  rinsing  the  plate,  and  outside  of  the  darkroom  but  near 
it  is  a  developing  tray  containing  half  an  inch  in  depth  of  a  fixing 


44 


PHOTOGRAPHY  35 

solution  made  of  four  ounces  of  hyposulphite  of  soda  dissolved 
in  a  pint  of  water.  All  of  this  in  full  white  light,  that  no  mistakes 
may  occur.  A  clock  or  watch  in  the  darkroom  should  be  so  placed 
that  it  may  be  read  by  the  red  light.  Close  the  darkroom  door  and 
shut  off  all  light  but  the  red.  When  the  eyes  have  become  accus- 
tomed to  the  weak  red  light,  open  the  plate-holder,  lift  the  exposed 
plate  by  the  edges,  place  it  in  the  developing  tray  film  side  up,  glance 
at  the  clock,  pour  on  all  of  the  developer,  making  half  an  inch  deep 
over  the  plate  and  wait.  If  the  plate  is  a  landscape,  soon  one  part 
of  it  will  begin  to  look  gray;  this  is  the  sky  coming  up  under  the 
action  of  the  developer.  This  should  be  seen  in  from  half  a  minute 
to  one  minute  after  the  developer  is  poured  on.  Soon  the  outlines 
of  objects  in  the  foreground  will  be  seen,  and  by  the  end  of  two 
minutes  the  picture  will  be  completely  visible.  This  is  not  half  enough 
development.  The  picture  w^ll  begin  to  fade  away,  to  sink  into  the 
film,  and  the  whole  plate  will  get  dark  on  the  surface.  When  the 
picture  has  had  five  or  sLx  minutes  and  seems  completely  spoiled, 
lift  the  plate  by  the  edges  and  see  whether  the  heavier  and  darker 
spots  have  come  tlirough  upon  the  back  of  the  plate.  If  the  picture 
is  visible  upon  the  back,  through  the  glass  of  the  plate,  it  is  likely 
that  the  negative  is  very  good.  Rinse  in  the  pan  of  clean  water  for 
fifteen  seconds  or  more,  that  the  developer  may  be  washed  out  of 
the  film  as  w^ell  as  washed  off  the  surface,  then  open  the  darkroom 
door  and  place  the  developed  plate  in  the  tray  of  hypo  outside; 
wash  the  hands  free  from  hypo  before  going  back  into  the  darkroom. 
At  this  time,  the  negative  will  show  the  black  image  upon  a  milky 
film.  When  held  to  the  light,  the  plate  is  opaque  and  the  image 
blurred.  After  five  minutes  in  the  fixing  bath  the  "milk"  of  the  film 
should  be  fading  rapidly,  and  ultimately  there  will  be  left  only  clear 
glass,  easily  seen  through,  with  the  image  sharp  and  black.  This 
is  sight  development.  The  plate  is  watched  all  the  time,  and  when 
the  image  is  strong  enough,  usually  judged  by  its  being  visible  through 
the  back  of  the  plate,  the  plate  is  taken  from  the  developer,  rinsed, 
and  placed  in  the  hypo  fixing  bath.  For  this  method  of  develop- 
ment, strong,  medium,  and  weak  developers  are  used.  Plates  which 
seem  slow  in  coming  up  are  put  in  strong  developer,  while  plates 
which  come  too  fast  are  placed  in  weak  developer.  Few  people 
understand  sight  development,  and  it  requires  an  experienced  eye 


45 


36  THE  MOTION  PICTURE 

to  decide  when  the  development  should  be  stopped.  It  is  not  a  good 
method  for  an  amateur,  but  it  should  be  used  for  the  first  plate,  that 
the  amateur  may  see  what  the  process  of  development  really  is,  even 
though  the  first  plate  be  spoiled  in  learning. 

Factorial  Development.  This  system  is  a  modification  of  the 
sight  development  system  which  brings  development  within  the 
range  of  the  amateur.  The  developer  should  be  mixed  according 
to  a  standard  formula,  it  should  be  at  65  degrees  by  the  thermometer, 
and  the  factor  should  be  known.  With  ready-mixed  developers,  the 
factor  usually  is  printed  on  the  wrapper  of  the  package. 

A  plate  properly  exposed  will  show  gray  in  the  sky  in  one-half 
minute  and  be  fully  developed  in  six  minutes.  A  plate  which  has 
had  a  little  too  much  exposure  will  be  fully  developed  in  five  minutes, 
but  it  will  show  its  first  gray  in  twenty-five  seconds  from  the  time 
the  developer  is  poured  on.  A  much  over-exposed  plate  will  be  fully 
developed  perhaps  in  three  minutes,  but  it  will  show  its  first  gray  in 
fifteen  seconds.  An  under-exposed  plate  may  need  twelve  minutes 
of  development,  because  with  the  less  exposure  the  image  builds 
up  more  slowly  and  also  appears  at  first  more  slowly,  taking  one 
minute  to  show  its  first  gray.  It  has  been  noted  that  the  total  time 
of  development  required  is  always — with  pyro  developer — about 
twelve  times  the  time  required  for  the  plate  to  show  its  first  gray, 
hence,  we  have  this  factorial  development  system  with  this  rule: 

Have  the  developer  at  65  degrees,  and  notice  the  time  from  pour- 
ing it  upon  the  plate  until  the  first  gray  is  shoivn.  Cover  up  the  tray 
and  icait  until  it  has  devoloped  twelve  times  that  long;  then  icash  it 
and  place  it  in  the  fixing  hath.  This  method  protects  the  plate 
from  the  red  light  except  for  the  first  minute,  and  even  this  may  be 
reduced  by  holding  the  tray  cover  between  the  tray  and  the  light 
and  only  removing  the  cover  for  a  second  every  five  or  ten  seconds 
until  the  first  gray  is  noticed.  This  is  a  thoroughly  practical  system 
for  amateurs.  Two  or  more  plates  may  be  started  at  once  in  different 
trays,  and  still  others  started  while  these  are  developing.  The 
time  for  taking  out  of  the  developer  may  be  written  on  a  slip  of  paper 
placed  on  top  of  each  tray  cover. 

Tank  Development.  By  the  name,  this  is  a  large  tank,  capable 
of  holding  several  plates,  or  several  dozen  plates,  and  filled  with 
developer.    The  developer  is  at  65  degrees.    The  plates  are  put  in. 


46 


PHOTOGRAPHY  37 

left  twenty  minutes,  taken  out,  rinsed,  and  placed  in  the  fixing  bath. 
This  is  a  simple  method  used  by  professionals  and  suitable  for 
amateurs.  It  merely  requires  care  that  the  developer  is  standard 
strength  and  standard  temperature. 

In  the  amateur's  darkroom,  this  tank  method  operates  as  fol- 
lows: Prepare  developer  according  to  tank  formula;  by  red  light 
place  a  plate  in  a  tray  and  fill  the  tray  with  tank  developer  at  65 
degrees;  wait  twenty  minutes;  remove  plate,  wash  and  fix  in  the  hypo 
bath.  In  hot  weather,  the  trays  should  be  cooled  to  65  degrees  or 
they  will  heat  the  developer;  in  cold  weather  it  may  be  necessary  to 
warm  them  to  65  degrees.  This  method  sometimes  is  called  the 
time  and  temperature  method.  With  a  few  plates  to  develop  it  is 
not  economical  of  time  nor  of  developer  but  the  results  will  average 
higher  in  quality  than  with  either  sight  or  factorial  method  of  de- 
velopment in  the  hands  of  an  amateur. 

Developing  without  the  Red  Lamp.  To  develop  without  the 
red  lamp  is  merely  a  matter  of  time  and  temperature,  and  handling 
the  plates  by  touch.  By  white  light,  pour  the  developer  into  the 
tray  (65  degrees);  have  the  cover  at  one  side  and  the  plate-holder 
at  the  other.  Put  out  the  light  and  in  darlvuess  remove  the  plate  from 
the  holder,  place  it  in  the  tray  of  developer,  and  place  the  clover  on 
the  tray.  Light  the  white  light,  look  at  the  watch,  wait  twenty  minutes, 
remove  the  plate  in  white  light,  rinse  quickly  and  thoroughly  and 
place  in  the  fixing  bath.  The  secret  of  this  process  is  that  white 
light   followed   quickly  by  a  fixing  bath  does  not  injure  the  plate. 

Washing  before  Fixing.  The  plates  should  be  washed  before 
fixing  in  order  to  keep  the  developer  out  of  the  fixing  bath.  The 
negatives  will  become  stained  in  the  fixing  bath  if  this  is  not  done. 

Fixing.  The  milky  silver  of  the  plate  must  all  be  removed. 
To  insure  this,  the  plate  should  be  allowed  to  remain  in  the  fixing 
bath  after  the  milky  appearance  is  gone  for  a  time  half  as  long  as 
was  required  to  remove  the  milky  appearance. 

Fixing  after  Washing.  The  hyposulphite  of  soda  must  be 
thoroughly  washed  out  of  the  film  or  the  negative  will  spoil  with 
age.  An  hour  in  running  water,  or  soaking  for  fifteen  minutes  each 
in  six  changes  of  water  should  insure  the  complete  removal  of  the 
hypo.  The  plate  then  is  set  on  edge  or  placed  in  a  rack  to  dry  in  a 
place  where  dust  will  not  settle  upon  its  sticky  wet  surface. 


47 


38  THE  MOTION  PICTURE 

Developing  Formulas.  A  convenient  method  for  compounding 
developers  is  to  open  an  ounce  box  of  pyro  or  other  developing 
agent  and  weigh  it  all  out  into  quantities  each  of  vt^hich  will  make 
one  pint  of  developing  solution  ready  for  use.  These  quantities 
may  be  wrapped  in  waxed  paper  and  packed  in  an  air-tight  can, 
bottle,  or  box.  Similar  powders  of  soda  may  be  made  up,  and  when 
developer  is  wanted  it  is  necessary  only  to  take  one  powder  from 
each  can  and  dissolve  in  a  pint  of  water. 

Pyro  Developer: 

First  powder — 14  grains  pyro 

Second  powder — 80  grains  sulphite  of  soda,  anhydrous 
55  grains  carbonate  of  soda,  anhydrous 

For  sight  or  factorial  development,  take  one  each  of  the  powders 
and  16  ounces  of  water.  Temperature  C5;  factor  12.  A  normal 
exposure  should  develop  for  about  six  minutes. 

For  tank,  or  "time  and  temperature"  development,  take  one 
each  of  the  powders  and  36  ounces  of  water.  Temperature,  65; 
time  20  minutes. 

Pyro  developer  can  be  used  only  once  except  for  sight  develop- 
ment, and  even  then  it  is  not  advised.  It  must  be  used  within  a  few 
minutes  after  dissolving  but  will  keep  indefinitely  before  dissolving. 

II ydro-Metol  Developer: 

First  powder —  14  grains  metol 

14  grains  hydroquinone 

Second  powder — 104  grains  sulphite  of  soda,  anhydrous 
104  grains  carbonate  of  soda,  anhydrous 

Dissolve  separately  one  each  of  the  powders  in  8  ounces  of  water; 
pour  together,  making  16  ounces  of  developer  for  sight  or  factorial 
development.    Temperature  65;  factor  15. 

For  tank,  add  water  to  make  36  ounces  of  developer;  tempera- 
ture 65;  time  20  minutes. 

Hydro-metol  developer  may  be  used  repeatedly  for  sight  devel- 
opment, but  works  more  slowly  after  the  first  use. 

Pluhi  Hypo  Fixing  Bath: 

4  ounces  hypo  crystals 
16  ounces  water 


48 


PHOTOGRAPHY  39 

This  bath  will  keep  indefinitely  until  used,  but  will  not  keep 
after  it  has  been  used.  It  may  be  used  for  several  plates  but  works 
more  slowly  after  the  first.  Wash  the  plates  well  before  putting  them 
into  the  plain  hypo  bath,  for  a  little  developer  in  the  plain  hypo 
will  stain  the  plates  if  they  are  left  in  the  bath  long. 

Acid  Hypo  Fixing  Bath: 

16  ounces  water 

4  ounces  hyposulphite  of  soda,  crystals 
80  grains  sulphite  of  soda,  anhydrous 
GO  grains  powdered  alum 

1  dram  citric  acid 

Dissolve  completely  the  hyposulphite  and  the  sulphite  before  add- 
ing the  alum  and  citric  acid,  or  the  bath  will  be  milky  and  less 
efficient. 

The  acid  fixing  bath  will  keep  before  and  after  using.  It  may 
be  used  repeatedly  as  long  as  it  will  dissolve  the  silver  from  the  film, 
l)ut  it  works  more  slowly  after  the  first  use.  It  is  less  likely  to  stain 
the  negative  from  developer,  but  will  do  so  if  too  much  developer 
gets  into  it,  and  after  it  becomes  weakened  with  repeated  use.  It 
should  not  be  used  after  having  become  discolored  with  developer, 
for  fear  of  stains  upon  the  negative. 

Removing  Pyro  Stains.  Negatives  stained  with  pyro  may  be 
cleared  after  washing  and  drying  in  the  usual  way  by  immersing  in 
a  bath  of 

3  ounces  iron  sulphate  (copperas) 
IG  ounces  water 

J  ounce  sulphuric  acid 

1  ounce  powdered  alum 

Wash  and  dry  as  after  fixing.    The  pyro  negative  has  an  olive 
green  natural  color  which  adds  much  to  its  good  printing  qualities. 
This  color  is  not  a  stain,  and  should  not  be  removed.    The  copperas 
clearing   bath   will   remove   the   yellow   blotches   which   sometimes 
appear  on  pyro  negatives  because  of  developer  in  the  fixing  bath. 
Intensifying  a  Negative- 
First  solution — 120  grains  mercuric  chloride 
120  grains  potassium  bromide 
1 2  ounces  water 


49 


40  THE  MOTION  PICTURE 

Second  solution — 1  ounce  sulphite  of  soda 
8  ounces  water 

Soak  the  negative  in  the  first  solution  until  it  is  white,  then  wash 
thoroughly  and  soak  in  the  second  solution  until  it  is  as  dark  as 
desired.     Wash  thoroughly  and  dry. 

Reducing  a  Dense  Negative: 

32  ounces  water 

1  ounce  hypo 
15  grains  of  red  prussiate  potash 

Dissolve  the  hypo  completely  in  half  the  water;  dissolve  the 
potash  in  the  remaining  water;  and  pour  the  potash  into  the  hypo. 
Reducing  Contrast  in  Negative: 

5  ounces  water 

3  grains  permanganate  of  potash 

6  drops  sulphuric  acid 

Intensification.  AMien  the  shadows  of  a  negative  are  only  gray, 
either  because  of  too  short  exposure  or  too  short  development,  or 
because  of  too  long  exposure  and  consequent  very  short  development 
under  the  sight  or  factorial  system  of  development,  the  printing 
quality  of  the  negative  may  be  improved  by  intensification  by  the 
mercury  process,  provided  always  that  the  negative  is  not  spoiled 
by  the  amateur  efforts  at  intensification.  Intensification  and  reduc- 
tion of  negatives  should  be  avoided  by  mastering  the  art  of  exposure. 

Reduction.  AMien  the  entire  negative  is  too  dense,  use  the 
potash  reducer.  When  the  clear  portions  print  satisfactorily  but  the 
dark  portions  are  too  dense,  giving  too  much  contrast  in  the  print, 
use  the  permanganate  reducer.  Except  with  skill,  the  negative  may 
be  ruined  with  either.  It  is  well  to  experiment  on  a  few  negatives 
of  small  value  before  attempting  either  reduction  or  intensification 
of  a  ])recious  picture — and  make  a  few  prints  from  the  negative  before 
risking  it  by  intensifying  or  reducing. 

Retouching  and  Spotting.  Retouching  consists  of  working  upon 
the  negative,  usually  with  pencils,  to  improve  its  quality  or  to  modify 
the  image.  First,  varnish  the  negative  with  a  good  retouching  var- 
nish. Then,  working  with  a  fine  pencil  point,  a  dark  line  in  the 
print,  as  a  wrinlde  in  a  face,  which  shows  as  a  light  line  in  the  negative, 
may  be  so  penciled  over  that  it  is  much  reduced  in  the  print  or  does 


60 


PHOTOGRAPHY  41 

not  show  at  all.  Retouching  is  a  task  which  usually  requires  special 
training  and  much  skill. 

Pin-holes.  Small  transparent  spots  sometimes  appear  in  a  nega- 
tive, resembling  pin-holes  in  appearance,  due  to  defect  in  the  gelatine 
of  the  plate,  to  grains  of  dust  on  the  plate  during  exposure  keeping 
the  light  from  striking  the  plate  under  the  dust  grain,  or  to  air  bubbles 
clinging  to  the  plate  during  development.  These  may  be  blacked 
in  by  a  weak  solution  of  India  ink  applied  with  a  small  camel's-hair 
brush  formed  down  to  an  extremely  fine  point.  Several  applications 
of  a  thin  color,  just  toucliing  the  spot  with  the  tip  of  the  brush  until 
the  film  absorbs  the  ink,  will  gradually  darken  the  pin-hole  until  it 
matches  the  part  of  the  negative  immediately  surrounding  it. 

An  opaque  spot  on  the  negative,  such  as  might  be  produced  by  a 
grain  of  dust  caught  by  the  film  while  drying,  or  by  an  overspotted  pin- 
hole, will  make  a  light  spot  on  the  print,  which  then  may  be  spotted  out 
upon  each  print  with  India  ink  in  the  same  manner  as  upon  the  negative. 

PRINTING 

Printing  consists  of  transferring  the  image  from  the  glass  nega- 
tive to  a  sheet  of  sensitive  paper,  and  then  rendering  the  paper  in- 
sensitive so  that  the  transferred  image  cannot  change.  This  trans- 
fer of  the  image  to  the  printing  paper  is  effected  without  changing 
or  injuring  the  negative,  and  as  many  finished  prints  as  are  desired 
may  be  made  from  one  negative. 

The  negative  is  not  a  reproduction  of  the  view,  but  a  record 
of  the  image  in  reversed  or  "negative"  form,  with  the  lights  of  the 
view  showing  dark  and  the  shadows  showing  light.  The  print  is 
made  from  the  negative  by  the  use  of  chemicals  which  discolor 
when  acted  upon  by  light,  giving  a  shadow  in  the  print  where  the 
negative  is  clear,  and  a  high  light  where  the  negative  shows  dark. 
The  print  thus  is  a  "negative  of  a  negative,"  and  shows  the  view 
in  its  proper  relation  of  light  and  shade. 

Processes.  Four  processes  of  printing,  or  producing  positive 
pictures  from  photographic  negatives,  are  in  general  use: 

(i)     Printing-out   toning  processes; 

(2)  Printing-out  self-toning  processes; 

(3)  Developing  or  gaslight  processes; 
(^)     Enlarging  or  lens-printing. 


51 


42  THE  MOTION  PICTURE 

In  each  case,  the  process  consists  of  subjecting  a  sheet  of  sensitized 
printing  paper  to  the  action  of  Hght  which  has  passed  through  the 
negative,  then  "fixing"  the  print  thus  made. 

Printing  Frame.  The  printing  frame  consists  of  two  parts, 
frame  and  back.  The  frame  is  open,  with  a  rabbet  of  proper  size 
to  take  the  glass  negative  as  a  piece  of  glass  is  placed  in  a  picture 
frame.  The  back  is  in  two  parts,  hinged  together,  each  part  having 
spring  clamps  for  fastening  it  into  the  frame.  The  negative  and 
then  the  print  paper  are  put  in  the  frame,  the  back  is  put  on,  and  the 
clamps  closed.  The  loaded  frame  is  placed  in  the  sunlight  and  the 
printing  paper  is  discolored  by  the  light  passing  through  the  negative. 
By  unclamping  one  fart  of  the  back  and  opening  it  on  its  hinge 
carefully,  the  progress  of  the  print  may  be  observed.  The  remain- 
ino"  clamped  part  of  the  back  holds  the  print  paper  and  the  negative 
in  alignment  while  the  free  end  of  the  print  is  looked  at. 

Printing=out  Papers.  These  papers  are  so  called  because  the 
pictures  "print  out"  or  become  visible  while  the  paper  is  printing 
in  the  sun.  The  printing  paper  consists  of  a  sheet  of  paper  with  a 
film  on  one  side,  similar  to  the  film  of  a  glass  plate,  but  very  much 
less  rapid,  or  less  sensitive  to  light.  In  handling  it,  the  red  light  is 
not  required,  as  ordinary  gas  light  or  the  light  of  an  oil  lamp  does 
not  affect  the  paper.  Subdued  daylight,  as  in  a  room  with  the  shades 
drawm,  usually  is  safe  and  does  not  affect  the  printing-out  paper. 

Chloride  Papers.  The  usual  "silver"  paper  consists  of  chloride 
of  silver  held  in  a  surface  of  gelatine,  collodion,  or  albumen.  It 
requires  the  three  steps  of  printing  in  the  frame,  toning  in  a  gold 
bath,  and  then  fixing  in  hypo,  in  addition  to  many  wash  waters,  to 
produce  the  finished  print  ready  for  mounting  upon  a  card. 

To  print,  lay  the  printing  frame  face  down,  lay  the  negative 
in  the  printing  frame  with  the  film  side  up,  lay  the  piece  of  printing 
paper  on  the  negative  with  the  sensitive  side  down,  then  a  pad  of 
half  a  dozen  pieces  of  newspaper  cut  the  right  size,  then  put  in  the 
back  and  fasten  the  clamps.  \ATien  thus  filled,  place  the  frame  in 
the  strongest  light  possible — direct  sunlight  is  best — with  the  glass 
side  toward  the  sun.  The  progress  of  printing  may  be  watched  by 
looking  at  one  half  of  the  print  from  time  to  time,  opening  the  frame 
and  turning  back  the  end  of  the  print,  as  shown  in  Fig.  28.  This 
exammation  must  be  made  in  the  shade,  at  least  with  the  frame 


52 


PHOTOGRAPHY  43 

held  in  the  shadow  of  the  operator's  body.  Continue  the  printing 
until  the  picture  is  much  darker  than  desired  in  the  finished  photo- 
graph. Print  until  the  details  in  the  half-tones  have  disappeared, 
indeed  until  the  print  seems  spoiled.  It  will  fade  back  in  the  toning, 
fixing,  and  washing  to  give  what  is 
wanted.  The  degree  of  over-print- 
ing can  be  learned  only  by  experi- 
ence and  practice. 

There  are  many  different  brands 
of  paper  offered  by  manufacturers, 
and  the  explicit  instructions  which 
accompany  each  package  of  print- 
ing  paper  should  be  followed.  At  ^'^- ''•  in^s?S/o?Pr1n?'" ''^^ 
first,  use  a  toning  bath  bought  ready 

mixed,  if  it  can  be  bought  especially  prepared  for  the  particular 
paper  used.  The  formulas  which  follow  are  representative,  and  are 
adapted  for  most  chloride  printing-out  papers. 

Washing  before  Toning.  Place  the  prints  in  running  water  or 
wash  through  several  changes  until  the  wash  water  no  longer  shows 
milkiness.  The  silver  unaffected  by  light  will  be  washed  out.  The 
prints  will  get  lighter  and  reddish  in  color.  Keep  the  prints  moving 
whik  in  the  wash  water. 

Tuning.     ]\Iake  two  stock  solutions. 

Gold  Solution 
7^  grains  pure  chloride  of  gold 
8     ounces  pure  water 

or  15  grains  chloride  of  gold  and  sodium  may  be  used  instead  of 
the  pure  chloride. 

Soda  Solution 

Pure  water 

Bicarbonate  of  soda  to  saturate 

By  saturation  is  meant  to  put  into  the  bottle  of  water  all  the  soda 
crystals  it  will  dissolve. 

For  a  dozen  4  by  5  prints,  shake  the  bottle  of  gold  and  take  one- 
half  ounce  of  the  solution  and  eight  ounces  of  water,  place  a  piece 
of  red  litmus  paper  in  it  and  add  the  soda  solution  drop  by  drop 
until  the  litmus  paper  begins  to  turn  blue.    If  the  litmus  paper  turns 


53 


44  THE  MOTION  PICTURE 

blue  too  rapidly,  add  a  drop  or  two  more  of  the  gold  to  slow  it.  A 
fresh  piece  of  litmus  paper  should  show  slight  blue  at  the  end  of  one 
minute.  This  toning  bath  must  be  nicely  balanced  between  the  gold 
and  soda,  and  then  left  for  half  an  hour  to  ripen  before  using.  Mix 
the  toning  bath,  and  let  it  ripen  while  washing  the  prints.  Place 
the  washed  prints  in  the  toning  bath  and  keep  them  moving. 

Stopping.  The  prints  will  change  in  color  through  a  range  of 
browns  to  purple  or  black.  They  may  be  stopped  brown  or  at  any 
shade  desired.  When  any  print  has  reached  its  desired  shade,  change 
it  to  the  stop  solution. 

Stop  Solution 

1  ounce  table  salt 

1  gallon  water 

Fixing.  When  all  prints  are  toned  and  stopped,  place  them 
in  a  fixing  bath  and  keep  them  moving  for  twenty  minutes.  The 
alum  fixing  bath  is  preferable. 

Soda  Fixing  Bath 
1  gallon  water 
1  pound  hyposulphite  of  soda 

Alum  Fixing  Bath 
1  gallon  water 

8  ounces  hyposulphite  of  soda,  crystals 
3  ounces  alum,  crystals 
2'  ounce  sulphite  of  soda,  crystals 
1  ounce  borax 

Dissolve  the  borax  in  a  pint  of  hot  water.  Dissolve  the  remain- 
ing chemicals  in  the  remaining  water,  then  pour  in  the  borax  solu- 
tion. This  bath  must  be  made  up  the  day  before  it  is  needed.  It 
keeps  indefinitely  both  before  and  after  using  but  should  not  be 
used  after  fixing  two  dozen  4  by  5  prints  to  the  pint. 

Final  Washing.  After  fixing,  the  hypo  must  be  thoroughly 
washed  out  or  the  prints  will  become  discolored  with  age.  Wash 
for  an  hour  in  running  water,  or  for  two  hours  in  changing  water, 
changing  the  water  at  first  every  five  minutes.  To  change  the  water 
on  the  prints,  use  two  dishes,  lifting  the  prints  one  by  one  from  the 
first  dish  into  the  second,  with  'jl  moment  of  draining. 


54 


PHOTOGRAPHY  45 

Combined  Toning  and  Fixing.  Two  stock  solutions  are  re- 
quired, soda  and  gold. 

Stock  Soda  Solution 
8  ounces  hyposulphite  of  soda,  crystals 
G  ounces  alum,  crystals 
2  ounces  granulated  sugar 
2  ounces  borax 
88  ounces  water 

Dissolve  the  borax  in  a  half-pint  of  hot  water;  dissolve  the 
remaining  chemicals  in  the  remaining  water,  cold,  and  pour  in  the 
borax.    Let  stand  over  night  and  pour  off  the  clear  liquid. 

Stock  Gold  Solution 
7h  grains  pure  chloride  of  gold 
64  grains  acetate  of  lead 
8  ounces  water 

Fifteen  grains  chloride  of  gold  and  sodium  may  be  used  instead 
of  the  pure  chloride  of  gold.     Do  not  filter.     Shake  before  using. 

For  fifteen  4  by  5  prints,  take  8  ounces  of  stock  soda  and  one 
ounce  of  stock  gold  and  put  in  the  dry,  raw  prints  without  washing 
before  toning,  ^^^len  properly  toned,  stop  them  in  a  solution  of 
1  ounce  of  salt  and  1  quart  of  water.  Then  if  possible  use  the  acid 
fixing  bath  for  ten  minutes  to  ensure  thorough  fixing.  Wash  finally 
for  an  hour  in  running  water,  or  the  equivalent  in  changing  waters. 

The  formula  given  for  the  combined  toning  and  fixing  bath  is 
a  thoroughly  tested  one,  and  may  be  bought  ready  mixed  under  the 
name  of  "Solio  Toning  Solution." 

Self=Toning  Paper.  These  are  printing-out  papers  which  take 
a  brown  tone  without  the  use  of  the  gold  toning  solution.  Their 
manipulation  is  much  simpler  than  the  ordinary  printing-out  papers. 
Some  of  them  require  only  washing  in  water  to  tone  and  to  render 
the  print  permanent.  Others  require  a  hypo  solution,  but  in  all 
instances  the  claim  of  self-toning  is  justified  by  the  simplicity  of  the 
operations  required  after  printing. 

Blue  Prints,  \^^len  purchased,  the  blue  print  paper  has  one 
side  coated  with  a  sensitizing  solution  containing  iron.  The  coated 
side  varies  from  a  light  yellow  to  green  in  color,  ^^^len  printed  under 
a  negative  in  a  printing  frame  in  the  sun  as  with  any  other  printing- 


55 


46  THE  MOTION  PICTURE 

out  paper,  the  image  comes  up  a  dull  dark  blue  and  the  shadows 
change  to  a  gray  or  bronze  appearance.  Print  until  the  deep  shadows 
are  bronze  and  until  the  detail  is  lost  and  the  print  seems  spoiled. 
Then  wash  in  clear  water  until  all  the  yellow  is  washed  out  of  the 
print  and  dry.  Too  long  washing  will  lose  the  details  and  half  tones 
of  the  picture.    The  picture  is  blue  and  white,  and  is  permanent. 

Sepia.  Print  as  for  blue  prints,  but  develop  in  a  very  weak 
solution  of  hyposulphite  of  soda  before  final  washing.  If  the  hypo 
is  too  strong,  the  prints  will  fade  in  the  bath.  The  sepia  print  must 
be  placed  in  the  hypo  and  then  in  the  wash  water  instantly  when  re- 
moved from  the  printing  frame;  it  will  not  "keep"  even  a  few  minutes. 

Developing  Papers.  The  amateur  who  is  employed  during  the 
day  will  find  his  time  best  disposed  and  will  get  the  most  enjoyment 
out  of  his  photographic  occupations  by  using  his  holidays  in  the  field 
with  his  camera  making  exposures  for  new  negatives  and  by  making 
his  prints  by  artificial  light  in  the  evenings.  The  printing  papers 
which  are  offered  for  contact  printing  by  artificial  light  are  sub- 
stantially slow  plate  films  spread  upon  paper  supports.  The  proc- 
esses of  exposure,  development,  and  fixing  are  substantially  the 
same.  Pyro  cannot  be  used.  The  hydro-metol  formula  for  developer 
for  plates  and  the  fixing  baths  either  plain  or  acid  are  proper  for 
developing  papers.  The  acid  fixing  bath  is  preferred.  Visual  de- 
velopment is  entirely  satisfactory  and  factorial  or  tank  development 
need  not  be  attempted.  With  normal  working  and  a  normal  negative, 
a  finished  print  is  in  the  fixing  bath  in  less  than  one  minute  after  the  neg- 
ative and  paper  are  put  in  the  printing  frame,  giving  a  decided  advan- 
tage for  the  amateur  over  the  slower  processes  of  printing-out  papers. 

The  sensitive  coating  of  developing  papers  is  made  much  slower 
in  response  to  light  than  the  coating  used  for  plates,  so  much  so 
that  red  light  is  unnecessary.  The  developing  trays  may  be  placed 
upon  a  table  6  feet  or  more  from  a  gas  jet,  but  when  developing 
the  operator  should  stand  with  his  back  to  the  gas  jet  and  with  the 
shadow  of  his  body  falling  over  the  developing  tray.  The  paper 
should  be  kept  covered  or  wrapped  in  black  paper  before  printing, 
and  should  be  loaded  into  the  printing  frame  in  the  shadow  of  the 
operator's  body. 

The  printing  outfit  re(|uired  consists  of  a  printing  frame.  Fig. 
28,  and  three  developing  trays.     Place  the  three  trays  in  a  row, 


56 


PHOTOGRAPHY  47 

developer  in  the  left,  water  in  the  middle,  and  fixing  bath  in  the 
right.  The  trays  are  very  convenient  if  of  a  larger  size  than  the 
prints  to  be  made,  and  the  quantity  of  solutions  contained  must  be 
Uberal.  Each  print  passed  through  the  developer  consumes  some 
of  the  strength  of  the  solution,  thus  weakening  it,  and  if  the  quan- 
tity of  the  developer  is  small  the  print  may  weaken  it  to  such  an 
extent  that  two  prints  from  the  same  negative  and  having  the  same 
exposure  will  develop  differently  because  of  the  weakening  of  a  small 
quantity  of  developer  by  the  first  of  the  prints.  A  developer  may 
be  used  repeatedly  until  it  becomes  too  slow  in  action. 

Developing  papers  may  be  printed  by  exposing  the  loaded 
printing  frame  to  daylight,  but  daylight  is  so  variable  from  minute 
to  minute,  if  there  are  clouds  in  the  sky,  that  an  element  of  uncer- 
tainty and,  therefore,  an  element  of  failure  is  brought  into  the  opera- 
tion of  making  the  prints.  Artificial  light  usually  is  constant  and  is 
preferable  for  that  reason.  With  a  4  by  5  printing  frame,  loaded 
with  a  medium  negative,  and  held  7  inches  from  an  ordinary  gas  or 
incandescent  electric  lamp,  a  trial  exposure  of  twenty  seconds  may 
be  made.  Remove  tlTe  paper  from  the  frame — it  shows  no  image — 
and  immerse  in  the  developer.  In  fifteen  seconds  it  should  be  com- 
pletely developed,  and  unless  transferred  quickly  to  the  water  it  will 
be  over-developed.  Rinse  for  a  few  seconds  in  the  water  to  remove 
the  developer  from  the  surface  and  place  it  in  the  fixing  bath.  After 
fifteen  minutes  in  the  fixing  bath,  wash  and  dry.  To  be  able  to  stop 
the  development  at  the  proper  instant  upon  an  over-exposed  print, 
lift  the  print  when  development  is  nearly  complete  and  let  the  develop- 
ing solution  drain  back  into  the  tray.  The  print  will  continue  develop- 
ing for  a  few  seconds  while  held  in  the  air,  because  of  the  developer 
which  clings  to  the  surface.  At  the  proper  instant,  plunge  it  into 
the  wash  water,  which  will  stop  development  almost  instantly,  and 
then  into  the  fixing  bath.  Tuni  an  under-exposed  print  face  down 
in  the  developing  tray  to  avoid  fog  during  prolonged  development. 

If  vnth  a  proper  exposure  the  whites  of  the  picture  are  gray 
before  the  shadows  are  deep  enough,  the  addition  of  a  few  drops 
of  a  solution  of  bromide  of  potassium — 1  ounce  bromide  of  potassium 
dissolved  in  10  ounces  water — will  tend  to  keep  them  clear.  Too  much 
bromide  in  the  developer  will  give  olive  tones  to  the  print.  Old  and 
slow  developer  will  give  purplish  tones  to  the  print.   Fresh  normal  devel- 


57 


48  THE  ISIOTION  PICTURE 

oper,  without  too  much  bromide  will  give  pure  blacks  and  whites  with 
untinted  half  tones  throughout  the  entire  range  from  light  to  shadow. 

The  time  of  development  should  be  about  fifteen  seconds  with 
normal  developer,  average  negatives,  and  regular  qualities  of  develop- 
ing papers.  The  amount  of  exposure  should  be  gauged  to  require 
this  time  of  development.  The  length  of  exposure  may  be  regulated 
to  some  extent  by  the  distance  between  the  light  and  the  printing 
frame.  Double  the  distance  for  the  same  negative  requires  four 
times  the  length  of  exposure,  and  half  the  distance  requires  but  one- 
quarter  the  length  of  exposure,  but  if  the  printing  frame  is  brought 
too  near  the  light  the  center  of  the  picture  will  be  printed  darker 
than  the  edges  and  the  heat  may  crack  the  glass  negative.  If  the 
leno-th  of  exposure  is  shorter  than  twenty  seconds,  increase  the 
distance  from  the  light  and  give  a  longer  exposure.  It  is  very  difficult 
to  time  accurately  an  exposure  of  less  than  twenty  seconds,  and  by 
adopting  a  longer  exposure  the  proper  length  may  be  given  more 
accurately.  The  adjustment  of  exposure  by  distance  also  involves 
printing  a  thin  negative  by  weak  light  and  a  dense  negative  by  strong 
light,  a  rule  usually  recommended  by  the  malTers  of  gaslight  papers. 
To  secure  uniformity  of  illumination  over  the  entire  negative,  a 
4  by  5  frame  should  not  be  exposed  closer  than  7  inches  from  the  light, 
and  a  5  by  7  frame  not  closer  than  10  inches. 

Several  different  brands  of  developing  papers  are  to  be  bought 
in  the  market,  all  differing  from  each  other  to  some  extent,  and 
for  each  brand  the  manufacturer  advises  a  specific  treatment,  de- 
veloper compound,  etc.  The  instructions  with  the  paper  should 
be  read  carefully  until  understood. 

Lens  Printing.  In  a  contact  print,  the  images  of  the  print  always 
are  of  the  exact  size  of  the  images  in  the  negative;  it  is  not  possible 
in  a  contact  print  to  make  a  print  larger  than  the  negative,  and  it 
is  possible  to  make  a  print  smaller  than  the  negative  only  by  omitting 
some  portion  of  the  view,  such  as  the  margins,  the  images  actually 
printed  being  of  the  size  of  those  of  the  negative.  By  printing  through 
a  lens  it  is  possible  to  change  the  size  of  the  images  of  the  picture, 
producing  a  print  either  smaller  or  larger  than  the  negative  from 
which  it  is  taken. 

Printing  through  a  lens  is  a  process  requiring  longer  exposures 
or  more  sensitive   printing   paper   than   contact  printing,  since  all 


« 


58 


FOOD  FOR  THE  HUNGRY 
Scene  from  Photoplay,  "How  He  Redeemed  Himself' 
Courtesy  of  the  Champion  Film  Company,  .\ew  York 


SCENE  FROM  PHOTOPLAY,  "THREE  OF  A  KIND" 

Courtesy  of  Independent  Moving  Pictures  Co.,   Xew   York 


PHOTOGRAPHY  49 

the  light  which  may  fall  upon  the  negative  cannot  be  passed  through 
the  negative  and  lens  effectively  to  act  upon  the  print  paper.  To 
bring  the  time  of  exposure  within  reasonable  limits,  a  paper  called 
bromide  paper  is  used.  This  is  much  more  sensitive  to  light  than  the 
brands  used  for  contact  printing.  \Mien  arrangements  are  made  to 
illuminate  the  negative  by  daylight,  the  use  of  bromide  paper  will 
bring  the  exposures  frequently  to  less  than  one  minute  in  length.  The 
length  of  exposure  will  depend  upon  the  size  of  the  enlarged  picture, 
as  well  as  upon  the  size  and  density  of  the  negative,  the  diaphragm 
stop  of  the  lens  used,  and  the  intensity  of  the  light. 

Bromide  paper  cannot  be  handled  in  daylight  or  in  gaslight, 
as  ordinary  developing  papers  are  handled,  but  must  be  worked 
in  the  darkroom.  It  is  developed  and  fixed  as  the  ordinary  develop- 
ing papers  are,  the  developing  and  fixing  formulas  given  for  the 
developing  papers  being  in  general  suitable  for  bromide  papers, 
but  in  the  case  of  the  bromide  papers  the  instructions  accompany- 
ing each  brand  of  paper  should  also  be  studied  until  understood, 
and  if  possible  the  exact  formulas  which  accompany  the  paper  should 
be  used  in  working  the  paper.  The  manufacturer  has  done  all  the 
experimenting  necessary  to  produce  good  results. 

Enlargements,  To  make  an  enlargement,  a  window  must  be 
closed  with  a  tight  screen  having  a  hole  in  it  a  little  larger  than 
the  negative,  and  at  such  a  height  that  the  camera  may  be  backed 
up  against  the  hole  to  close  it.  A  cloth  thrown  about  the  camera 
when  thus  placed  will  seal  the  window  light  tight.  Cut  the  middle 
partition  out  of  a  double  plate-holder  so  that  when  a  negative  is 
placed  in  the  plate-holder  it  will  be  held  by  the  edges  only.  Remove 
the  ground  glass  from  the  camera,  place  a  negative  in  the  plate- 
holder  and  place  the  plate-holder  in  the  camera.  Place  a  white 
screen  vertically  in  front  of  the  camera,  and  focus  the  negative  upon 
it  by  racking  the  front  of  the  camera  out  to  the  proper  focus.  To 
make  the  image  upon  the  screen  larger,  move  the  screen  farther  from 
the  camera;  to  make  the  image  smaller,  move  the  screen  nearer  to 
the  camera.  If  the  window  does  not  open  directly  to  the  free  sky, 
a  mirror  may  be  placed  outside  the  window  to  reflect  the  free  sky 
into  the  negative.  The  arrangement  with  mirror  is  shown  in  Fig. 
29.  The  only  light  entering  the  room  is  that  passing  through  the 
negative  and  the  lens. 


59 


50 


THE  MOTION  PICTURE 


To  make  a  test  exposure,  place  a  piece  of  ruby  glass  in  front  of 
'the  lens  and  tack  upon  the  screen  a  strip  of  bromide  paper.  Remove 
the  niby  glass  from  the  lens  for  one-half  minute  and  cover  one- 
quarter  of  the  strip  of  bromide.  Again  remove  the  ruby  glass  from 
the  lens  for  one-half  minute  and  then  cover  the  second  quarter  of 
the  bromide  strip,  which  now  has  had  one  minute.  Remove  the 
ruby  glass  from  the  lens  for  one  minute  and  cover  the  third  quarter 
of  the  bromide  strip,  which  now  has  had  two  minutes.  Remove 
the  ruby  glass  from  the  lens  for  two  minutes,  giving  the  remaining 


Fig.  29.     Camera  Arranged  for  Daylight  Enlarging 

quarter  of  the  bromide  strip  four  minutes  in  all.  Develop  the  strip, 
and  it  will  tell  which  exposure  is  correct,  or  between  which  two  values 
the  correct  time  will  be  found,  ^^^^en  this  is  known,  tack  a  full-size 
piece  of  bromide  paper  on  the  screen  and  expose  for  the  determined 
length  of  time,  developing,  fixing,  and  washing  the  resulting  print. 

Lens  caps  fitted  with  ruby  or  orange  glass  may  be  bought  for 
capping  the  lens  while  pinning  the  bromide  paper  to  the  screen  for 
exposure.  The  advantage  of  such  a  colored  glass  cap  is  that  it 
leaves  the  image  visible  upon  the  screen  and  the  bromide  paper 
may  be  correctly  placed.  This  is  of  particular  value  when  only  a 
part  of  the  whole  negative  is  to  be  printed  in  the  enlargement. 


60 


PHOTOGRAPm^  51 

SPECIAL  APPLICATIONS  OF  PHOTOGRAPHY 

Lantern  Slides.  To  tell  a  long  story  in  a  short  way,  the  lantern 
slide  is  a  print  on  glass  instead  of  on  paper.  Lantern-slide  plates 
are  sensitized  usually  with  the  same  chemicals  used  in  bromide 
paper.  They  may  be  printed  by  contact  printing  as  any  developing 
paper  is  printed,  or  may  be  printed  by  lens  printing.  In  either 
case,  they  must  be  handled  by  darkroom  methods,  because  they 
are  as  sensitive  as  the  bromide  paper  and  nearly  as  sensitive  (about 
one-twentieth)  as  the  dry  plates  used  for  negatives. 

The  American  lantern  slide  is  always  of  a  standard  size,  3^  by  4 
inches.  Foreign  slides  sometimes  have  other  dimensions,  t^pon 
this  size  of  plate,  the  actual  picture  for  projection  by  the  lantern 
seldom  is  larger  than  2f  by  2|  inches.  AMiere  the  image  to  be  printed 
upon  the  lantern  shde  is  contained  within  this  space  in  the  negative, 
the  slide  may  be  printed  by  contact,  but  where  the  image  in  the 
negative  is  larger  than  3  by  3  inches,  it  will  be  necessary  to  employ 
the  process  of  lens  printing.  As  the  lantern  slide  is  but  a  bromide 
print  on  glass,  all  of  the  instructions  for  lens  printing  on  paper  apply 
directly  to  the  making  of  a  lens-printed  lantern  slide.  The  lens 
printing  of  the  lantern  slide  will  be  necessarily  "cop\ang  down" 
or  reducing  rather  than  enlarging,  meaning  that  the  screen  upon 
which  the  picture  is  focused  will  be  closer  to  the  lens  and  will  rec[uire 
a  longer  draw  for  the  camera  bellows.  If  necessaiy,  a  box  with 
both  ends  open  may  be  introduced  against  the  window,  holding  the 
negative  against  the  window,  the  back  end  of  the  camera  being 
against  the  other  end  of  the  box,  thus  providing  an  extension  to  the 
length  of  the  total  draw  obtainable  by  the  box  and  the  bellows  to- 
gether. Correction  for  the  thickness  of  the  glass  of  the  lantern- 
slide  plate  must  be  made  to  secure  proper  focus,  but  a  ground  glass 
may  be  focused  upon  and  the  sHde  plate  substituted  for  exposure. 

Another  method  of  lens  printing  for  lantern  slides  when  the 
reductions  are  considerable,  is  to  place  the  lantern-slide  plate  in 
the  plate-holder  of  the  camera,  place  the  negative  in  the  window, 
and  focus  the  ground  glass  of  the  camera  upon  it  with  the  lens  end 
of  the  bellows  toward  the  negative,  inserting  the  lantern-slide  plate 
with  the  dark  slide  and  exposing  as  in  a  field  exposure,  thus  actually 
making  a  photograph  of  the  negative. 


61 


52  THE  MOTION  PICTUEE 

Place  a  lantern-slide  mask  upon  the  completed  glass  print,  place 
a  cover  glass  over  it,  and  bind  the  edges  with  lantern-slide  binding 
strip,  and  the  slide  is  finished. 

Stereographs.  These  double  pictures  are  adapted  to  present 
two  slightly  different  images  of  the  same  object  to  the  two  eyes 
when  viewing  the  stereograph,  the  two  images  being  different  in 
just  the  details  wherein  the  two  eyes  of  the  observer  would  see  the 
phvsical  object  differently  by  reason  of  the  difference  between  the 
viewpoints  of  the  observer's  eyes.  The  two  pictures  of  the  stereo- 
graph are  made  simultaneously  by  a  camera  having  two  lenses  side 
by  side.  A  two-image  negative  thus  is  produced,  a  two-image  print 
is  made  from  it,  and  the  two  images  are  cut  apart  and  pasted  upon 
a  card  for  viewing  through  the  lenses  of  the  stereoscope.  By  reason 
of  the  lens  reversal  of  the  images  in  the  camera,  the  images  of  the 
print  must  be  transposed  before  pasting  upon  the  card.  The  dis- 
tance between  the  lenses  usually  is  about  3^  inches ;  between  the  prints 
on  the  stereograph  mount,  about  2f  inches.  This  gives  a  slightly 
exaggerated  perspective,  increasing  the  illusion  of  perspective  and 
solidity  when  the  stereograph  is  viewed  properly.  ^Miile  the  paired 
lenses  are  desirable,  stereographs  of  still  objects  or  scenes  may  be 
made  by  an  amateur  by  two  successive  exposures  of  the  same  camera, 
the  camera  being  moved  3  or  4  inches  between  the  two  exposures. 
Use  a  small  lens  stop,  as  great  depth  of  focus  is  desirable  in  a  stereo- 
graph. 

Panoramas.  The  ordinary  photographic  lens  places  upon  the 
ground  glass  an  image  which  includes  about  sixty  degrees  of  the 
horizon.  Wide-angle  lenses  are  lenses  of  short  focus  for  comparatively 
large  plates  and  sometimes  cover  one  hundred  degrees  or  more. 
Negatives  including  more  of  the  horizon  than  any  single  fixed  lens 
can  make  have  been  obtained  by  a  swinging  lens.  A  camera  of  this 
nature  has  a  sensitive  film  held  in  a  semicircle,  and  has  its  lens 
mounted  in  a  swinging  frame  which  gives  an  exposure  of  but  a  nar- 
row vertical  slit  upon  the  film.  As  the  lens  swings,  nearly  one-half 
of  the  horizon  is  impressed  upon  the  film  in  a  continuous  image. 
Another  type  of  panoramic  camera  has  gears  for  revolving  it  upon 
the  tripod  top  and  winds  a  roll  of  film  behind  the  slit  of  a  lens  while 
the  camera  is  revolving.  With  this  camera  an  image  may  be  made 
including  the  entire  horizon. 


62 


PHOTOGRAPHY 


53 


Panoramic  prints  may  be  made  by  the  amateur  by  making 
two  or  more  plate  exposures  and  pasting  the  prints  upon  a  card 
with  the  edges  carefully .  trimmed  and  matched.  In  making  such 
exposures  intended  for  panoramic  mounting,  the  vertical  line  of 
matching  should  be  in  mind  when  arranging  the  image  upon  the 
ground  glass.  Only  the  double  lens  should  be  used,  as  the  distor- 
tion of  the  single  lens  will  be  seen  when  the  edges  are  matched  in 
the  finished  picture. 

Telephotography.  Quite  the  opposite  of  panoramic  photog- 
raphy is  telephotography,  which  is  the  art  of  enlarging  a  small  por- 
tion of  the  view  to  fill  the  entire  plate.  The  production  of  a  large 
image  of  a  distant  object  is  the  result  which  telephotography  en- 


Fig.  30.     Glasses  of  a  Telephoto  Lens 

deavors  to  obtain.  This  is  done  directly  in  the  camera  by  adding 
a  third  lens  cell  to  the  double  lens;  a  negative  cell,  having  a  lens 
thinner  in  the  middle  than  at  the  edges,  spreads  the  middle  part  of 
the  image  to  cover  all  of  the  plate.  The  arrangement  of  glasses  in 
such  a  lens  is  shown  in  Fig.  30.  The  third,  or  negative,  lens  is 
mounted  at  the  back  end  of  a  long  lens  tube  and  an  ordinary  double 
lens  is  mounted  at  the  front.  By  the  use  of  the  telephotographic 
lens,  a  bellows  extension  of  12  inches  may  be  sufficient  to  make 
an  image  upon  the  ground  glass  as  large  as  would  be  made  by  a  lens 
of  48  or  60  inches  in  focal  length.  The  time  of  exposure,  however, 
is  proportionately  longer,  and  the  enlarged  image  upon  the  ground 
glass  is  proportionately  dim.  Telephotography  is  a  process  for  the 
enlargement  of  the  image  in  the  camera  before  it  is  recorded.  The 
result  does  not  differ  from  an  enlargement  made  from  a  small  por- 
tion of  a  negative  taken  from  the  same  viewpoint,  unless  iii  greater 
sharpness  of  detail. 


63 


54  THE  MOTION  PICTURE 

Orthochromatic  Photography.  White  light  is  made  up  of  a 
mixture  of  colors,  and  colored  objects  are  objects  which  separate 
the  white  light  which  falls  upon  them  and  give  to  the  eye  but  a  part 
of  its  component  colors.  Of  all  the  visible  colors,  the  blue  and  violet 
are  the  most  active  in  affecting  the  photographic  plate.  There  are 
also  invisible  rays,  called  ultra-violet  rays,  accompanying  white  light 
which  are  very  powerful  to  affect  the  sensitive  plate.  With  the  blue 
light  more  powerful  in  action  upon  the  sensitive  plate,  it  is  clear  that 
when  an  exposure  is  made  upon  a  subject  containing  blue,  yellow, 
and  red,  as  a  bouquet  of  flowers,  the  light  from  blue  blossoms  will 
make  a  darker  image  in  the  negative  and,  therefore,  a  lighter  image 
in  the  print  than  light  from  the  red  or  yellow  blossoms.  Thus,  a 
scene  having  colors  will  not  be  reproduced  in  its  proper  light  and 
shadow  values  by  the  ordinary  processes  of  amateur  photography. 
A  rosebush  in  bloom  with  white  roses  will  give  proper  results,  ])ut 
an  adjacent  bush  in  bloom  with  red  roses  will  appear  in  the  photo- 
graph to  have  no  blossoms  at  all,  since  the  bright  red  of  the  blossoms 
is  no  more  effective  upon  the  sensitive  plate  than  the  dull  green  of 
the  rose  leaves,  and  the  roses  may  be  distinguished  upon  the  bush 
only  by  their  shape,  as  green  apples  upon  a  midsummer  tree. 

To  remedy  this  feature  of  the  ordinary  photographic  processes 
and  to  render  photography  suitable  for  colored  objects,  a  plate 
sensitive  to  yellow  and  slightly  sensitive  to  red  is  made,  and  there 
is  made  also  a  colored  screen,  or  "ray  filter"  for  the  lens  which  has 
the  faculty  of  holding  out  a  large  portion  of  the  blue  and  ultra-violet 
rays  and  permitting  all  of  the  yellow  and  red  rays  to  pass,  ^^^^en 
such  a  plate,  called  an  orthochrotnatic  plate,  is  exposed  to  a  lens 
image  of  light  which  has  passed  through  a  proper  ray  filter,  the 
blues,  yellows,  and  reds  will  all  have  equal  effect  upon  the  plate, 
and*  the  resultant  picture  will  show  the  view,  not  in  colors  at  all, 
l)ut  in  proper  values  of  light  and  shade  regardless  of  color  in  the 
view.  The  objection  to  the  universal  use  of  the  orthochrome  plate 
and  the  ray  filter  is  that  from  three  to  eight  times  the  exposure  is 
required. 

Colored  Photographs.  Any  print  may  be  colored  by  brush  and 
suitable  transparent  dyes.  If  it  is  the  wish  to  reproduce  the  actual 
colors  of  the  scene,  it  is  necessary  that  the  negative  be  made  with 
an  orthochromatic  plate,  or  it  will  be  impossible  to  reproduce  the 


64 


PHOTOGRAPHY  55 

reds,  since  they  will  be  black  in  the  print.  Photography  in  natural 
colors  by  camera  and  development  processes  without  recourse  to 
hand  coloring  is  a  problem  which  has  been  solved  in  several  ways, 
yet  no  solution  is  entirely  satisfactory.  The  most  nearly  satisfactory 
processes  involve  first,  the  separation  of  the  light  of  the  image  into 
two,  three,  or  four  different  colors;  second,  the  photographing  of  the 
separate  colors  by  separate  negatives,  the  negatives  being  uncolored; 
third,  the  making  of  prints,  one  for  each  negative  and  each  print 
of  a  single  color  in  itself  but  of  a  color  different  from  the  other  prints 
of  the  set;  and  fourth,  combining  the  separately  colored  prints  or 
arranging  them  in  a  viewing  device  such  that  all  of  the  prints  may 
be  viewed  at  once.  The  colors,  thus  being  placed  upon  each  other, 
blend  in  the  eye  to  form  all  the  hues  of  the  original  view. 

Tri=Color  Photography.  Pieces  of  orange-red,  green,  and  violet 
glass  are  required,  of  such  size  as  to  cover  the  lens  of  the  camera. 
Tri-color  results  will  largely  depend  upon  the  accuracy  and  purity 
of  the  hue  of  these  colored  ray  filters.  Having  selected  and  focused 
the  scene,  expose  three  orthochromatic  plates,  one  after  another, 
each  of  them  with  one  of  the  colored  glasses  in  front  of  the  lens. 
With  a  set  of  color  filters  used  by  the  author,  the  exposure  required 
is  four  times  normal  with  the  violet  filter,  thirty  times  normal  with 
the  green  filter,  and  five  hundred  times  normal  with  the  orange 
filter.  The  negatives  when  developed  will  all  look  alike.  Make 
three  lantern-slide  plates  and  cover  each  Vv'ith  a  cover  glass  of  the 
color  through  which  the  negative  of  that  slide  was  made.  In  all 
slides,  white  objects  are  clear  glass;  shadows  are  black.  Brightly 
colored  objects  remembered  in  the  view  will  have  different  half- 
tone values  in  the  three  plates.  A  violet  object  is  lightest  in  the 
violet  plate.  A  blue  object  is  darkest  in  the  orange  plate.  A  green 
object  is  lightest  in  the  green  plate.  A  yellow  object  is  darkest  in 
the  violet  plate.  A  red  object  is  lightest  in  the  orange  plate.  The 
three  slides  are  projected  by  three  lanterns  upon  the  same  screen 
and  at  the  same  time,  when  the  colors  will  unite  to  give  all  the  hues 
of  the  original  view.  The  process  is  simple  in  theory,  but  requires 
very  careful  and  accurate  working  to  produce  acceptable  results. 

Autochrome  Plates.  By  the  use  of  these  plates  an  amateur 
may  make  pictures  in  natural  colors  as  simply  as  making  a  negative 
and  paper  print.     Each  exposure  in   the  camera  produces  not  a 


65 


56  THE  MOTION  PICTURE 

negative  but  a  glass  positive  print  in  colors,  suitable  for  direct  view 
or  for  lantern  slide  if  of  proper  size.  The  exposure  is  made  through 
a  special  orange  screen,  and  the  time  of  exposure  is  about  one  hun- 
dred times  the  normal  exposure  for  the  same  view  and  lens  stop 
with  ordinary  plate  and  no  ray  filter. 

Autochrome  plates  differ  from  ordinary  plates  by  having  inter- 
posed between  the  sensitive  coating  and  the  glass  a  thin  layer  of 
transparent  microscopical  starch  grains,  dyed  orange-red,  green, 
and  violet,  spread  without  over-lapping,  and  mixed  in  such  propor- 
tion that  the  layer  appears  colorless.  The  sensitive  coating  is  ex- 
tremely thin,  and  made  of  a  very  fine-grained  emulsion.  When  such 
a  plate  is  exposed  in  the  camera,  the  glass  side  toward  the  lens,  the 
light  before  reaching  the  sensitive  coating  passes  through  the  colored 
starch  grains,  which  act  individually  as  minute  color  filters,  each 
one  absorbing  all  colors  but  its  own.  A  microscopical  selection  takes 
place,  and  after  development  there  will  be  found  under  each  grain 
a  corresponding  black  image  of  a  density  proportionate  to  the  amount 
of  color  received  and  transmitted  by  this  particular  grain.  Were 
the  plates  fixed  at  this  stage,  the  picture  when  examined  by  light 
passing  through  the  plate  would  show  only  the  colors  complement- 
ary to  those  of  the  original,  since  the  true  colors  are  masked  by  the 
black  images  they  created  beneath  the  grains.  The  next  step  is  to 
dissolve  the  black  silver  by  an  acid  permanganate  solution;  then 
the  plate  is  exposed  to  white  light  and  re-developed,  blackening  the 
white  silver  left  by -the  permanganate  solution.  The  image  now  is 
reversed.  Each  color  grain  transmits  light  precisely  of  the  same  hue 
and  proportionate  intensity  as  the  light  transmitted  by  the  grain 
when  the  exposure  was  made  in  the  camera,  and  the  view  is  seen  in 
its  natural  colors. 


66 


O  ; 


H    5. 

O  ^ 
<  -- 


Q  c 
O  I 

O   g 
CO 

o 


I 


MOTOGRAPHY 

Pictography,  or  motion  photography,  is  compared  with  fixed  or 
still  photography  at  every  point.  It  is  contrasted  with  fixed  photog- 
raphy in  three  important  phases:  First,  the  product  desired;  second, 
the  methods  of  production  required,  which  involve  the  author  of 
the  film  story  and  the  producer,  with  their  assistants;  and  thini, 
the  means  adopted,  which  involves  the  photographer  and  his  special- 
ized   photographic   equipment. 

PRODUCT  DESIRED 

Fundamentally,  motography  is  the  art  of  depicting  motion 
by  means  of  photography.  Usually  the  associated  step  of  projec- 
tion is  used  for  viewing  the  motion  depicted  in  the  motion-picture 
film,  but  with  this  the  photographer  of  the  motion  picture  is  hardly 
concerned.  His  picture  when  completed  may  be  viewed  by  pi-o- 
jection,  or  by  direct  vision  in  a  proper  stepping  device,  or  by  close 
and  careful  study  of  the  successive  pictures,  either  alone  or  with 
two  consecutive  pictures  placed  over  each  other  to  reveal  the  differ- 
ences due  to  motion  in  the  subject.  IMotion  pictures  may  be  made 
for  scientific  study  or  for  purposes  of  amusement. 

Chronophotography.  In  this  word,  "chrono"  means  "time," 
and  the  object  of  the  art  of  chronophotography  is  to  photograph 
the  condition  of  a  moving  subject  at  successive  times  in  its  move- 
ment. Such  a  process  would  produce  if  possible  a  sharp  photograph 
of  the  subject  at  regular  intervals,  so  that  a  careful  study  of  the 
series  of  pictures  might  reveal  just  what  changes  had  taken  place 
in  the  short  inteiTal  of  time  between  the  taking  of  two  successive 
pictures.  The  extreme  positions  taken  by  the  subject  and  the  posi- 
tions of  the  subject  at  critical  instants  may  be  obsen-ed  in  such  a 
series  of  pictures,  enabling  a  scientist  to  study  his  subject  in  a  manner 
that  is  hardly  possible  by  any  means  other  than  chronophotography. 

Chronophotographic  machines  iiave  been  devised  to  make 
pictures  at  a  rate  as  fast  as  five  hundred  pictures  of  the  same  subject 

Copyright,  1911,  by  Ainerican  School  of  Correspondence. 


69 


2  THE  MOTION  PICTURE 

in  one  second.  With  a  flying  bird  beating  its  wings  at  the  rate  of 
two  beats  per  second,  such  a  photograph  would  present  two  hundretl 
and  fifty  different  positions  of  the  wings  of  the  bird  in  beating  the 
air,  and  certain  of  the  images  would  show  the  extreme  upper,  the 
extreme  lower,  and  the  extreme  outward  positions  of  the  wings, 
as  well  as  showing  the  difference  in  positions  of  the  wings  in  beating 
downward  upon  the  air  and  in  returning  to  the  upper  position. 
These  photographs  should  be  sharp  and  distinct  as  far  as  possible, 
that  even  the  details  of  the  wing  feathers  may  be  studied.  Such  a 
series  of  photographs  should  be  of  value  to  a  student  of  flying  ma- 
chines, but  it  is  not  recorded  that  any  such  good  has  come  of  it. 

In  the  study  of  a  walking  man,  chronophotographic  studies 
have  been  made  by  the  miUtary  department  of  France  and,  as  a 
result  of  those  studies  and  experiments  conducted  in  connection 
with  them,  it  has  been  found  possible  to  increase  the  endurance 
of  infantry  on  march  by  teaching  the  soldiers  an  improved  march- 
ing  gait. 

In  chronophotography,  it  is  desired  to  photograph  the  sub- 
ject as  it  is  rather  than  as  the  eye  sees  it,  for  because  of  its  motion 
the  eye  of  the  observ-er  may  be  deceived  as  to  the  actual  positions 
taken  and  as  to  their  actual  order  of  occurrence.  It  is  the  object 
of  chronophotography  to  reveal  for  the  study  of  the  scientist  that 
which  the  eye  is  unable  to  see. 

Kinephotography.  This  is  an  older  name  for  motography. 
In  this  word,  "kine"  means  "motion,"  and  the  object  of  motography 
is  to  make  a  record  of  the  motion  of  the  ^ubject  in  such  a  manner  that 
by  the  use  of  the  record  the  motion  may  be  reproduced  to  the  eye 
viewing  the  picture. 

In  motography,  it  is  desired  to  photograph  the  subject  as  the 
eye  sees  it  rather  than  to  reveal  it  as  it  is,  and  if  because  of  the  motion 
of  the  subject  the  eye  is  in  any  way  deceived  when  viewing  the  phys- 
ical subject,  then  the  true  artist  motographer  will  produce  such 
a  picture  as  will  also  deceive  the  eye  in  the  same  way  and  to  the 
same  extent  when  viewing  the  motion  picture. 

The  making  of  motion  pictures  is  thus  divided  into  two  classes: 
motion  pictures  for  scientific  study — chronophotography;  and  mo- 
tion pictures  for  amusement- — motography — for  motography  is  so 
largely  an  industry'  of  amusement  that  its  other  phases  may  be  con- 


70 


MOTOGRAPHY  3 

gidered  as  subordinate.  Chronophotography  will  be  considered 
later  as  a  subordinate  phase  of  motography. 

Subjects.  Primarily  the  proper  subject  for  a  motion  picture 
is  motion,  or  a  subject  containing  motion.  This  is  not  a  limitation, 
however,  for  still  subjects  are  very  forcibly  presented  in  motion 
pictures  when  the  camera  itself  has  movement  so  that  each  of  the 
successive  images  upon  the  jfiilm  is  made  from  a  different  viewpoint. 

Subjects  are  classified  in  the  trade  as  travels,  industrials,  cur- 
rent events,  dramas,  comedies,  and  trick  pictures.  Travels,  in- 
dustrials, and  current  events,  are  pictures  in  which  the  motographer 
finds  his  subject  ready  for  his  camera.  It  is  necessary  only  to  choose 
a  viewpoint  for  the  camera,  and  to  choose  an  opportune  moment, 
particularly  for  proper  lighting,  or  if  an  interior  is  involved  it  may 
be  necessary  to  provide  artificial  lighting.  Dramas,  comedies, 
chases,  and  trick  pictures  on  the  other  hand  are  classes  in  which 
the  motographer  must  create  his  subject.  These  form  the  bulk 
of  the  film  industry  and  occupy  the  picture  screens  of  the  motion- 
picture  theaters  almost  exclusively.  These  classes  overlap  each  other, 
while  science  studies  are  a  class  apart.  In  many  instances,  a  film 
picture  might  be  classified  in  either  of  two  or  even  more  classes, 
according   to   one's  own  judgment. 

Travels.  Travels  include  pictures  showing  the  natural  scenery 
of  the  country  as  the  chief  interest  of  the  picture.  The  title  takes 
a  form  indicating  a  journey  or  a  visit  to  a  country  or  place.  The 
film  is  made  up  of  many  scenes,  as  though  the  motographer  were 
enjoying  a  holiday  with  his  camera  and  were  photographing  every- 
thing of  interest  to  him,  particularly  everything  typical  of  the  place 
or  country  in  which  his  visit  is  made,  or  of  the  line  of  travel  over 
which  his  journey  carries  him. 

Industrials.  Industrials  are  in  substance  similar  to  travels, 
the  distinction  being  rather  that  the  one  takes  the  work  of  man  as 
a  subject  and  the  other  takes  the  work  of  nature.  An  industrial 
picture  shows  the  production  of  something  involving  the  industry 
of  man.  Factory  industries  when  made  the  subject  of  motion  pic- 
tures may  include  the  production  in  the  mine,  farm,  or  forest  of  the 
raw  material;  views  of  the  machinery  with  which  the  raw  material 
is  worked  through  its  various  stages  of  manufacture;  views  of  the 
material  itself  in  its  successive  stages  of  manufacture;  and  views  of 


71 


4  THE  MOTION  PICTURE 

the  finished  product.  Mining,  farming,  kimbering,  and  shipping, 
when  made  the  subject  of  industrial  motion  pictures,  verge  upon 
the  classification  of  tra\els.  A  decision  as  to  whether  the  picture 
should  be  classified  as  travel  or  industrial  should  be  based  upon 
the  manner  in  which  the  motographer  has  handled  his  subject. 

Current  Events.  Current  events  are  substantially  news  pic- 
tures. ^Miether  an  event  of  interest  becomes  a  part  of  a  travel  pic- 
ture, an  intlustrial  picture,  or  a  current-event  picture  comparable 
to  a  newspaper  illustration,  depends  largely  upon  the  manner  in 
which  it  is  handled.  "A  Visit  to  London"  (travel)  may  properly 
include  views  of  water  sports  on  the  Thames;  "The  Ice  Industry" 
(industrial)  may  open  with  a  scene  of  skating  on  the  ice  and  close 
with  spectators  consuming  ice-cold  beverages  while  they  watch  a 
tennis  game;  a  professional  ball  game  or  a  prize-fight  seems  "indus- 
trial" within  itself;  "The  Funeral  of  King  Edward  VII.,"  a  splendid 
and  impressive  film,  is  properly  classified  as  a  news  picture  (current 
events). 

Dramas.  Dramas  are  pictures  which  have  a  story  to  tell.  They 
are  comprised  of  a  series  of  connected  incidents  which  tell  the  story 
step-by-step — as  a  staged  production  in  pantomime— yet*  do  not 
contain  the  element  of  levity  or  burlesque  to  such  an  extent  as  to 
render  the  film  classifiable  as  a  comedy.  The  main  object  of  the 
drama  is  to  tell  a  story  in  a  pleasing  manner  and  in  such  a  way  that 
the  story  forms  the  fundamental  feature  of  the  entertainment,  and 
not  the  actors,  nor  the  stage  setting,  nor  the  separate  incidents. 

Comedies.  Comedies  are  pictures  which  are  designed  to  tell 
a  story  with  the  sole  intent  of  creating  laughter,  ^^^len  in  the  nature 
of  drama,  tlie  plot  and  its  execution  by  the  actors  is  light  or  bur- 
lesque in  nature.  Pictured  jokes,  pictured  puns,  pictured  accidents 
with  ludicrous  results,  awkwardness  and  confusion  on  the  part  of 
the  actors,  all  furnish  subject  matter  for  this  class  of  film  pictures. 

Chases.  Chases  are  a  division  of  the  comedy  class,  in  which 
the  stoiy  involves  the  pursuit  of  some  of  the  actors  by  others.  A 
long  series  of  kidicrous  incidents  may  be  strung  together  in  a  film, 
depicting  the  eft'orts  of  the  pursued  to  evade  his  pursuers  and  the 
tribulations  of  the  pursuers,  ending  the  film  either  with  or  without 
a   capture. 

Trick  Pictures.     Trick  pictures  are  l)ascd  upon  the  ability  of 


72 


MOTOGRAPHY  5 

the  motographer  to  deceive  the  audience  with  film  pictures  produced 
by  special  manipulation  of  the  motion-picture  camera.  Trick  pic- 
tures usually  are  comedies  in  that  the  trick-picture  art  usually  is 
used  to  produce  laughter.  Under  this  class,  however,  come  pictures 
of  transformations  forming  parts  of  more  serious  dramas,  and  some 
trick  pictures  themselves  are  wonders  of  illusion  so  profound  that 
they  have  a  charm  of  their  own  and  offer  a  class  of  entertainment 
neither  drama,  nor  comedy,  nor  chase,  and  classifiable  only  as 
"trick"  or  "spectacular." 


METHODS  OF  PRODUCTION 

Early  Methods.  Drawn  Pictures.  INIotion  pictures  are  almost 
as  old  as  pictures,  but  until  the  advent  of  photography  the  motion 
picture  was  nothing  but  a  scientific  curiosity  or  a  toy.  The  oldest 
motion-picture  device  of  which  we 
find  record  is  the  zoefrope,  Fig.  1,  a 
whirling  device  having  a  number  of 
slits  in  a  cylinder,  and  opposite  each 
slit  a  picture.  As  the  cylinder  whirls, 
the  pictures  are  seen  in  rapid  succes- 
sion, and  the  whirling  may  be  so 
rapid  that  the  pictures  seem  all  piled 
upon  each  other.  WTien  the  device 
is  turned  at  proper  speed,  persistence 
of  vision  holds  one  picture  until  the 
next  is  seen.  By  drawing  the  pic- 
tures by  hand,  taking  care  to  simulate  successive  positions  of  an 
object,  the  object  will  seem  to  have  motion  when  the  device  is 
whirled  and  the  pictures  are  seen  successively. 

Since  the  advent  of  the  first  picture-viewing  device  and  before 
the  advent  of  photography,  a  large  number  of  designs  of  viewing  or 
even  of  projecting  apparatus  for  motion  pictures  had  been  pro- 
duced, but  no  devices  for  making  the  pictures  to  be  viewed.  The 
making  of  the  many  pictures  by  hand  was  a  well  nigh  impossible 
task.  In  such  a  series,  the  fixed  objects  must  be  exactly  alike  in 
all  of  the  pictures  of  the  series  or  there  will  seem  to  be  motion  in 
the  fixed  things  of  the  picture.    The  moving  objects  must  be  similar 


The  Zoetrope 


73 


6  THE  MOTION  PICTURE 

in  all  details  and  must  vary  in  position  only,  and  the  variation  in 
position  must  be  in  harmony  throughout  all  the  moving  objects  of 
the  scene.  A  compromise  was  effected  by  one  progressive  experi- 
menter, who  projected  his  fixed  objects  from  a  fixed  lantern  slide 
and  projected  upon  that  fixed  scene  his  carefully  drawn  moving 
images.  In  this  way  he  simulated  the  entrances,  ^gestures,  and  exits 
of  actors  upon  a  stage  setting,  and  in  the  light  of  more  modern  his- 
torv  it  is  but  reasonable  to  think  that  perhaps  he  supplied  also  spoken 
words  for  the  actors,  thereby  anticipating  in  a  measure  the  modern 
"talking  pictures." 

Photographic  Process.  ^Yith  the  discovery  of  photography 
came  the  realization  that  here  was  a  new  agent  for  the  production 
of  pictures  for  the  moving-picture  exhibiting  apparatus.  The  diffi- 
culty to  be  met  was  in  photographing  moving  scenes  with  photo- 
graphs taken  in  such  quick  succession  that  the  movement  between 
two  successive  images  would  be  so  small  that  the  two  images  would 
seem  to  blend  into  one  as  the  hand-drawn  pictures  of  the  zoetrope 
did  when  the  new  photographs  were  substituted  for  the  old  hand- 
drawii   images. 

Separate  Cameras.  The  first  solution  was  by  ^Nluybridge  who, 
in  1877,  arranged  a  row  of  twenty-four  cameras  with  string-trigger 
shutters,  the  string  of  each  shutter  being  stretched  across  a  race 
track.  A  horse  rapidly  driven  down  this  race  track  broke  the  strings 
and  released  the  shutters  as  the  horse  was  opposite  each  camera, 
thus  taking  a  series  of  pictures  within  a  very  short  period  of  time. 
When  these  plates  had  been  developed  and  compared  and  matched 
up,  it  was  found  that  a  set  of  them  could  be  arranged  to  show  the 
successive  positions  of  the  running  horse.  This  set  comprising 
only  a  limited  number  of  images  was  suitable  to  be  shown  in  any  of 
the  motion-picture  viewing  devices  then  known. 

Multiple  Camera.  The  next  solution  was  that  of  LePrince, 
about  ten  years  later,  who  arranged  a  multiple  camera.  This,  in 
substance,  was  a  battery  of  sixteen  automatically  reloading  cameras, 
using  strip  film.  Each  camera  would  make  one  picture  and  while 
the  remaining  fifteen  cameras  were  making  fifteen  more  pictures 
in  regular  sequence,  the  first  camera  would  automatically  bring  a 
fresh  film  into  position  to  make  the  seventeenth  picture  in  its  turn, 
and  so  repeatedly  the  sixteen  cameras  would  operate  to  make  a  con- 


74 


MOTOGRAPHY  7 

tinuous  series  of  photographs.  This  LePrince  camera  was  the 
hnmediate  ancestor  of  the  modern  motion-picture  camera,  being 
built  in  a  single  case  with  battery  of  sixteen  lenses  and  sixteen  shut- 
ters, all  operated  by  a  single  continuously  turned  crank.  The  pic- 
tures were  taken  upon  four  strips  of  film.  By  printing  four  positive 
strips  and  passing  them  through  the  same  battery  of  lenses  and 
shutters,  projection  could  be  accomplished,  or  the  pictures  could 
be  cut  apart  and  pasted  into  a  single  strip  such  as  is  used  in  a  modern 
projecting  machine. 

Modern  Methods.  The  features  of  the  modern  motion  picture 
wliich  are  improvements  upon  the  earlier  forms  and  which  render 
it  adaptable  for  its  present  amusement  purposes  are  the  production 
of  the  images  by  photography;  the  flexible  negative  film  which  per- 
mits a  large  number  of  pictures  to  be  taken  quickly  in  succession 
upon  a  single  strip  of  negative  record;  the  transparent  support  for 
the  positive  print  or  positive  film,  permitting  the  picture  to  be  pro- 
jected in  an  enlarged  scale  upon  a  screen  so  that  it  may  be  viewed 
by  large  audiences;  and  the  system  of  registering  holes  in  the  margin 
of  the  films  by  which  registry  or  alignment  of  the  numerous  pictures 
of  the  series  is  attained  in  the  projecting  machine. 

Motion  pictures  were  fully  reduced  to  a  commercial  entertain- 
ment means  when  it  was  possible  to  take  a  motion  camera  and  a  reel 
of  negative  film,  to  select  a  subject  and  expose  the  film  upon  the 
subject,  to  print  the  negative  upon  a  strip  of  positive  film  and  pro- 
duce a  positive  print,  and  to  project  that  print  upon  a  picture  screen 
to  be  viewed  by  an  audience.  They  were  well  received  by  the  pub- 
lic from  the  beginning,  and  the  industry  grew  rapidly  from  the  first. 

In  the  beginning  it  was  sufficient  to  photograph  anything  with 
movement,  and  the  wonder  of  the  projected  picture  was  sufficient  to 
hold  the  attention  of  the  audience.  A  railway  train  passing,  a  fire 
engine,  a  waterfall,  or  the  view  from  the  car  window  was  sufficient. 
The  subjects,  which  were  confined  to  "travel"  and  science  studies, 
and  occasional  comedies,  were  enthusiastically  received  by  the  public. 
Dramas  were  not  known. 

With  the  advent  of  "the  exclusively  motion-picture  theater,  the 
demand  for  drama  and  comedy  grew.  It  became  necessary  for 
motion-picture  manufacturers  to  acquire  studios  suitable  for  stag- 
ing drama  and  comedy,  to  employ  writers  to  furnish  themes  for 


75 


8  THE  MOTION  PICTURE 

motion-picture  plays,  to  employ  actors  and  stage  directors  to  present 
the  themes  properly  before  the  motion  camera,  and  to  employ  scene 
painters  and  property  men  in  a  manner  very  similar  to  the  opera- 
tion of  a  standard  theater  except  that  the  seating  capacity  is  absent 
and  the  play  is  produced  but  once  in  the  studio. 

Division  of  Labor.  ^\Tien  an  industry  has  reached  such  a  mag- 
nitude that  many  people  are  employed  in  its  work — Pathe  Freres 
have  more  than  five  thousand  employes  in  France — some  employes 
will  develop  greater  al^ility  in  some  lines  than  in  others,  and  the 
lines  of  activity  become  so  divergent  that  they  are  best  cared  for 
separately.  As  in  any  manufacturing  industry,  the  manufacture 
of  motion-picture  films  for  exhibition  in  a  modern  factory  has  its 
division  of  labor,  and  a  film  picture  is  the  joint  product  of  the  various 
departments  and  specialists  who  in  turn  take  it  and  perfect  it  with 
their  skill.  Four  widely  different  classes  of  ability  are  involved, 
represented  by  four  men,  the  author,  the  producer,  the  salesman, 
and  the  photographer,  with  their  assistants. 

The  author's  stint  begins  with  the  conception  of  the  thought 
and  continues  until  the  thought  is  reduced  to  motographable  form. 
The  "producer"  takes  charge  of  the  total  task  at  that  point  and  carries 
the  work  forward  until  the  motographic  scenes  of  the  picture  have 
been  recorded  upon  the  sensitive  film  by  the  photographer.  The 
photographer's  duty  comprises  the  carrying  of  the  camera  to  the 
producer's  scenes  wherever  they  may  be,  recording  the  scenes  photo- 
graphically, developing  the  negatives,  and  printing  as  many  finished 
pictures  as  the  salesman  may  require.  The  salesman  most  likely 
will  be  called  the  advertising  manager  of  the  film  manufacturing 
company,  but  his  ultimate  duty  is  to  sell  the  film  product  which 
the  author,  producer,  and  photographer  have  worked  together  to 
make. 

THE  AUTHOR 

For  the  production  of  travels  strictly,  as  travels  were  produced 
in  the  early  days,  perhaps  no  author  is  required.  The  modern 
tendency  toward  drama  has  modified  the  custom.  It  is  in  dramas, 
comedies,  chases,  and  trick  pictures  that  the  author  becomes  promi- 
nent, and  as  these  form  the  bulk  of  the  motion-picture  industry  the 
author  is  always  first  to  be  considered.  Much  special  training  is 
necessary  to  become  a  successful  motion-picture  author. 


76 


MOTOGRAPHY  9 

His  Problems.  Limitations  of  the  Art.  The  limitations  of  the 
producer  must  be  understood  fully  by  the  author.  Few  fiction  writers 
create  a  successful  drama  for  the  histrionic  stage  at  the  first  attempt, 
and  their  failures  are  due  largely  to  a  lack  of  knowledge  of  the  limi- 
tations, of  the  technique,  of  the  dramatic  stage.  Much  more  limiting 
are  the  requirements  of  the  motion-picture  producer  with  his  studio 
stage  and  voiceless  actors. 

Many  ambitious  writers  have  submitted  stories  to  the  film  manu- 
facturers in  the  hope  that  they  might  be  found  suitable  for  produc- 
tion in  motion  pictures,  but  very  few  of  such  stories  are  accept- 
able. The  film  manufacturer  is  still  obliged  to  create  his  o^ti  plots, 
to  write  his  own  stories  and  scenarios,  and  to  employ  persons  who 
have  become  trained  to  authorship  under  the  limitations  exercised 
by  the  producer  and  the  tools  he  has  to  work  with.  Any  limitation 
upon  the  maker  of  the  film  must  of  necessity  be  also  a  limitation 
upon  the  writer  of  the  story  which  is  to  be  told  by  the  film.  One 
Umitation  is  the  matter  of  color,  for,  unless  the  story  is  to  be  written 
especially  for  color  production,  no  essential  part  or  feature  of  the 
story  or  action  may  depend  upon  color.  Another  limitation  is  time 
of  action,  with  an  upper  limit  of  twenty  minutes  or  one  reel  of  1,000 
feet  of  film  for  drama,  and  usually  ten  minutes  or  a  half  reel  of  film 
for  comedies  or  trick  pictures.  Other  limitations  are  the  size  of  the 
stage  which  may  be  used,  the  costimies,  stage  settings,  and  stage 
properties,  and  last  and  most  important  of  all  the  necessity  of  con- 
veying thought  by  action,  gesture,  and  facial  expression  rather 
than  by  voice. 

Plot.  The  author  must  deliver  an  acceptable  plot.  The  proper 
plot  for  a  motion  picture  is  one  suitable  for  a  short  story  of  one 
thousand  words  in  the  current  magazines  rather  than  one  suitable 
for  a  popular  novel.  The  complete  action  must  occur  in  twenty 
minutes,  and  this  compels  the  story  to  be  told  as  a  short  story,  no 
matter  how  much  there  is  to  tell.  The  masterpieces  of  motion- 
picture  drama  consist  of  simple  stories,  simply  told.  The  rule  carries 
into  comedy,  trick,  travel,  and  industrial  pictures.  A  central  thought 
forms  the  foundation  of  the  story;  this  is  embodied  in  a  series  of  in- 
cidents involving  as  few  leading  characters  as  possible,  for  it  is  con- 
fusing to  the  audience  to  be  obliged  to  carry  too  many  characters 
in   mind.     An   unnecessary  character  only  confuses   the  spectator 


77 


10  THE  MOTION  PICTURE 

and  leads  the  attention  away  from  the  principal  characters  and  from 
the  central  thought  which  they  are  to  give.  The  series  of  incidents 
should  require  as  few  stage  settings  as  possible,  for  the  same  reason 
that  multiplicity  leads  to  confusion  and  confusion  is  undesirable. 
The  time  is  short,  twenty  minutes,  and  the  real  story  of  the  play 
must  be  told  fully  and  plainly,  not  smothered  with  unnecessary  scenes 
or  incidents  nor  obscured  with  side  thoughts.  Lubin's  "Woman 
Hater"  offers  a  twenty-minute  picture  of  a  thousand  feet  of  film 
stao-ed  with  a  single  stage  setting  and  only  four  characters,  and  it  is 
one  of  the  masterpieces.  Essanay's  "Justified"  does  the  same  with 
only  three  characters  and  a  couple  of  supes. 

The  plot  is  brief.  It  is  only  the  central  idea,  the  skeleton,  the 
foundation.  The  title  is  not  the  least  in  importance,  for  it  is  the  part 
which  is  advertised  outside  the  theater  and  the  detail  upon  which 
dependence  is  placed  to  draw  the  patrons  from  the  sidewalk  past 
the  ticket  window  into  the  house.  \Mien  a  striking  tide  is  created 
in  the  author's  mind,  the  plot  is  half  written. 

Scenario.  The  scenario  elaborates  the  plot  into  "dramatized" 
form,  for  the  motion-picture  play  should  be  written  as  if  for  the 
stage,  not  in  "fiction"  form  as  for  a  magazine  article.  In  the  scenario, 
the  characters  are  listed,  the  requi^-ed  scenic  settings  are  listed,  and 
the  action  scene  by  scene  is  recited.  "Tides"  are  given  in  the  order 
in  which  they  are  met  from  scene  to  scene.  Under  the  name  of 
"titles"  are  included  notes  written,  newspaper  pages,  or  any  matter 
which   the  audience  must  read   in   the  progress  of  the  picture. 

SPECIMEN  DRAMA  SCRIP 
The  following  typical  drama  with  but  four  leading  characters 
was  produced  by  the  American  Biograph  Company.  The  scene 
settings  are  simple,  only  three  scenes  being  set  for  studio,  and  those 
not  requiring  anything  unusual  in  the  way  of  scenery.  The  out- 
side scenes  are  such  as  may  be  found  in  any  village.  That  one  scene 
setting  is  used  sevcBal  times  and  the  total  ninnber  of  scenes  thus 
increased  is  not  objectionable.  The  plot  will  withstand  success- 
fully a  rigid  analysis.  The  drama  is  divisible  into  four  chapters, 
as  die  four  acts  in  a  staged  play,  each  chapter  having  a  definite  part 
in  the  progress  of  the  telling  of  the  story.  No  scenes  of  crime  or 
violence  are  involved,  and  no  scenes  of  a  nature  to  depress  the  spirits. 


I 


78 


MOTOGRAPHY  11 

TITLE 
A  Midnight  Cupid 

PLOT 

A  tramp  wanders  into  a  club  man's  rooms  and  falls  asleep.  Club  man, 
bored  with  society,  finds  tramp  and  finds  in  tramp's  pocket  letter  asking  tramp 
to  return  home.  Club  man  for  diversion  assumes  tramp's  identity  and  goes 
to  his  home.  Falls  in  love  with  tramp's  childhood  playmate.  Tramp  returns 
home.  Club  man,  ousted  in  disgrace,  elopes  with  girl.  Pursued  by  girl's 
father.  Overtaken  in  club  man's  rooms  after  marriage.  Girl's  father  sees 
wealth  and  social  position  of  club  man  and  forgives. 

SCENARIO 

Cast  of  Characters 

Club  man  (C  M) 

Tramp  (T) 

Girl  (G) 

Girl's  Father  (G  F)  as  farmer 

Policeman 

Two  servants  to  club  man 

Guests  at  reception 

First  farmer 

Second  farmer 

Grocer 

Minister 

Lady,  Avell  dressed,  age  40 

Tw'o  or  three  men,  well  di'essed 

Children 

Scene  Sets 

Club  man's  rooms  (Studio) 

Parlor  (Studio) 

Interior  cottage  bedroom  (Studio) 

City  park  (two  sets) 

Outside  village  store 

Outside  village  cottage 

Village  street 

Field 

Synopsis 

CHAPTER  I.  Prologue,  giving  the  conditions  under  which  the  true 
action  of  the  draraa  is  to  occur. 

Scene  1.     City  park,  first  set.     Discovered,  T  reading  letter. 

Title:  "Dear  Joe:  As  the  father  of  the  girl  who  was  your  childhood's 
sweetheart,  I  ask  you  to  come  back  home.    (Sig.)    Wm.  Broadhurst." 

{Back  to  Scene  1 .)  T  reads  letter  sorrowfully,  searches  pockets,  no  money; 
puts  letter  in  upper  outside  coat  pocket  with  edge  visible;  lies  on  bench,  sleeps. 


79 


12  THE  MOTION  PICTURE 

Enter  policeman,  raps  T  on  foot  with  club,  "Move  on."    Exit  policeman  left. 
Exit  T  right. 

Scene  2.  CM  room,  well  jurnished,  table,  chairs,  sofa;  door  back,  door 
right.  Discovered,  CM  opening  mail.  Bored  look.  Enter  servant,  brings  full 
decanter,  places  on  table;  CM  looks  at  decanter  in  disgust.  CM  signs  to 
servant;  exit  servant  back,  returns  with  coat  and  hat;  CM  dons  and  exits  back. 
Exit  servant  back. 

Title:     "Seeking  Food." 

Scene  3.  Same  as  Scene  2.  Enter  slowly  T  right.  Calls  (face  business). 
Raps  on  table,  indicates  hunger,  sees  decanter,  makes  great  show  of  resistance 
to  temptation,  drinks  and  falls  asleep  on  sofa. 

Scene  4.  Parlor.  Discovered,  many  guests.  Enter  CM.  Several  ladies 
overly  attentive  to  CM,  bores  CM  much.    Exit  CM. 

Scene  5.  Same  as  Scene  3.  Discovered,  T  asleep.  Enter  back  CM  bored. 
Presently  discovers  T,  calls.  Enter  two  servants.  Servants  surprised.  CM 
sees  letter  in  T  pocket,  takes  letter  and  reads. 

Title:    (Repeat  title  showing  letter  in  Scene  1 .) 

{Back  to  Scene  5.)  CM  (face  and  stage  business)  forms  plan  for  a  lark. 
CM  puts  money  in  T  pocket  in  place  of  letter.  Orders  servants.  Exeunt 
servants  right,  carrying  T.     Exit  CM  back. 

Scene  6.  City  park,  second  set.  Enter  servants  left  carrying  T;  place 
T  on  bench.     Exeunt  servants  left. 

Title:    "The  Club  Man  Plans  to  Take  the  Tramp's  Place." 
Scene  7.    Same  as  Sce?ie  5.     Enter  CM  back  dressed  as  tramp.     Enter 
servants  right.     CM  explains,  servants  try  to  dissuade  but  fruitlessly.     Exit 
CM  back;  servants  in  despair. 

CHAPTER  II.    The  normal  or  main  action  of  the  drama. 
Scene  8.     Outside  Village  Store.     Discovered,  grocer  and  first  and  sec- 
ond farmers.    Enter  CM  as  tramp.     Shows  letter  to  grocer.    Grocer  surprised, 
tells  farmers,  farmers  surprised,  all  welcome  CM.     Grocer  indicates  direction, 
CM  exit  right. 

Scene  9.  Outside  Village  Cottage,  back  yard.  Discovered,  GF  in  chair. 
Enter  from  cottage  G  with  newspaper,  show  of  affection,  G  gives  paper  and 
exit  into  cottage.  Enter  CM  right,  inquires  of  GF,  introduces  self,  GF  refuses 
to  accept  identity,  CM  shows  letter,  GF  accepts  identity  and  welcomes 
CM,  GF  calls,  enter  G  from  cottage,  introduction,  surprise,  welcome,  face 
business  of  admiration  by  CM,  all  exeunt  into  cottage. 
Title:     "Unpleasant  Duty." 

Scene  10.  Same  as  Scene  9.  Enter  from  cottage  GF  with  hoe,  and  CM. 
Exeunt  right. 

Scene  11.     Field.     Enter  GF  and  CM  left.     GF  hands  hoe,  to  CM  and 
indicates  work  in  field.    CM  takes  off  coat  and  begins  awkwardly,  GF  scolds, 
CM  works  harder,  exit  GF  left. 
Title:     "Pleasant  Duty." 

Scene  12.  Same  as  Scene  11.  Discovered,  CM  hoeing  in  field.  Busi- 
ness of  weariness,  lights  cigarette,  sits  on  coat.  Enter  G  left.  CM  hides 
cigarette  quickly,  welcomes  G.  G  indicates  leaving  together,  exeunt  together 
left. 

Scene  13.     Village  Street.    CM  and  G  pass  across  together,  right  to  left. 


80 


MOTOGRAPHY  13 

Scene  14.  Same  as  Scene  8  with  children  playing  in  extreme  background. 
Discovered,  grocer  and  first  and  second  farmers.  Enter  CM  and  G  right. 
Exeunt  into  store  CM  and  grocer  and  first  farmer.  Second  farmer  proposes 
marriage  to  G,  indicating  his  wealth.  Refused  by  G.  Exit  G  into  store.  En- 
ter from  store  G,  grocer,  first  farmer  and  CM  carrying  packages.  Exeunt  CM 
and  G  right.  Enter  CM  right,  pays  grocer,  exit  CM  right.  Stage  business  in- 
dicating that  CM  is  accepted  and  well  liked. 

Scene  15.  Same  as  Scene  9.  Discovered,  GF  in  chair.  Enter  CM  and  G 
right,  welcome  by  GF,  exit  G  into  cottage,  exit  CM  right,  stage  business  by 
GF  indicating  that  CM  is  accepted  and  well  liked. 

CHAPTER  III.    The  interfering  action  of  the  drama. 

Scene  16.  Same  as  Scene  6 .  Discovered,  T  asleep.  T  wakes,  remembers 
letter,  finds  paper  money  in  pocket  instead,  is  surprised,  exit  right  in  glee. 

Scene  17.  Same  as  Scene  14-  Discovered,  grocer,  first  and  second 
farmers.  Enter  T  right.  Recognizes  grocer,  grocer  denies  T  identity,  exit 
grocer  into  store.  T  recognizes  first  farmer,  first  farmer  denies  T  identity, 
guards  his  watch  and  exit  right.  T  recognizes  second  farmer,  but  second 
farmer  avoids  hand  and  eludes  T,  making  exit  into  store.  T  alone  on  stage, 
face  business  of  wonder  and  surprise.     Exit  T  right. 

Scene  18.  Same  as  Scene  15.  Discovered,  GF  in  chair.  Enter  T  right, 
recognizes  GF,  GF  denies  T  identity.    T  lip  language  and  gesture,  "I  am  me." 

Title:     "The  Tramp  Proves  His  Identity." 

{Back  to  Scene  18.)  T  (stage  business)  tells  of  accident  while  swimming 
and  diving  as  a  boy  and  shows  scar  on  head,  shows  birthmark  on  neck.  GF 
satisfied  with  identification,  calls  to  cottage,  G  enters  from  cottage,  introduc- 
tion, G  surprised.  GF  angry,  calls  off  stage  right,  CM  enters  right,  shows 
agitation  on  seeing  T,  GF  rages,  GF  orders  CM  away,  G  tries  to  follow,  GF 
interferes,  exit  CM  right,  exeunt  G,  GF,  and  T  into  cottage. 

Scene  19.  Interior  cottage  bedroom,  practical  door  at  back  opening  in- 
ward xoith  lock  and  key,  jiracticcd  window  right.  Enter  G  and  GF,  GF  rages, 
G  cries,  GF  puts  key  in  door  on  outside,  exit  raging  and  closes  door.  G  tries 
door  to  show  it  locked,  sinks  crying  by  bedside. 

CHAPTER  IV.  The  resolution  of  the  plot  and  the  conclusion  of  the 
drama. 

Scene  20.  Same  as  Scene  13.  Enter  CM  right,  walking  rapidly,  hesi- 
tates, shows  much  money,  laughs,  turns,  exit  right. 

Scene  21.  Same  as  Scene  19.  Discovered,  G  crying  by  bedside.  Enter 
CM,  head  only  at  window,  calls,  G  responds  slowly,  confusedly,  then  quickly. 
CM  invites  elopement,  G  consents,  gets  wrap,  exit  through  window. 

Scene  22.  Same  as  Scene  20.  Discovered,  first  and  second  farmers 
approaching  in  extreme  background.  Enter  CM  and  G  right,  talk,  CM  shows 
and  offers  money  and  by  accident  drops  paper  from  pocket  when  taking  money 
from  pocket,  G  refuses  money,  embraces  CM,  exeunt  G  and  CM  left.  Farmers 
reach  foreground,  converse  excitedly.  First  farmer  exit  right.  Second  farmer 
sees  paper,  reads,  and  exit  right. 

Scene  23.  Same  as  Scene  IS.  Discovered,  GF  in  chair.  Enter  first 
farmer  right,  tells  GF  of  elopement.    GF  exit  to  cottage. 

Scene  24.  Sayne  as  Scene  21.  Enter  GF  by  door,  looks  around  room, 
notices  open  window,  stage  business  of  despair  and  rage,  exit  through  door. 


81 


14  THE  MOTION  PICTURE 

Scene  25.  Same  as  Scene  23.  Discovered,  first  farmer.  Enter  GF  from 
cottage,  raging.  Enter  second  farmer  with  paper,  shows  paper  to  GF.  GF 
reads.     All  exit  right,  GF  raging. 

Title:    "The  Marriage." 

Scene  26.  Same  as  Scene  5.  Enter  CM  as  tramp  and  G  back.  CM 
rings;  enter  two  servants  back;  CM  orders  first  servant;  exit  first  servant; 
CM  orders  second  servant;  exit  second  servant.  Stage  business  of  love  scene. 
Enter  first  servant  and  woman,  stylish,  age  40,  apparently  relative  of  CM, 
introduction  to  G,  enter  two  men  well  dressed.  Enter  second  servant  and 
minister.  CM  explains  to  minister;  produces  paper,  apparently  license  to 
wed,  and  hands  to  minister;  m.inister  reads,  indicates  readiness,  performs 
marriage  ceremony;  congratulations  by  all.  In  midst  of  confusion,  enter 
GF  raging  and  first  and  second  farmers.  GF  tries  to  seize  G;  G  clings  to  CM; 
servants  and  guests  interfere;  CM  tells  GF  they  are  married;  G  tells  GF  they 
are  married;  minister  tells  GF  they  are  married;  GF  in  despair  and  rage, 
farmers  in  despair. 

Title:     "Convinced  of  Son-In-Law's  Wealth,  Father  Forgives." 

{Back  to  Scene  26  loith  minister  talking  to  GF.)  Minister  explains  to  GF 
that  CM  owns  the  house.  GF  surprised,  asks  servants,  who  answer  yes;  asks 
men,  asks  woman,  asks  CM;  all  answer  yes.  Still  hesitates,  gesture  of  appeal 
from  G,  GF  takes  G  and  CM  in  arms  and  dances.    All  joyous.    (End  of  picture.) 

SPECIMEN  COMEDY 

The  requirement  of  a  comedy  is  that  there  be  a  laugh  at  the 
close,  and  as  many  before  that  as  possible.  In  a  comedy  which  is 
neither  chase  nor  trick,  the  plot  should  show  the  successive  steps  of 
story  telling:  first,  the  prologue  setting  forth  the  conditions  under 
which  the  action  of  the  story  is  to  occur;  second,  the  action  of  the 
story,  which  may  be  in  several  parts;  and  last  the  resolution  and 
conclusion. 

TITLE 

The  Old  Maid's  Dream 

PLOT 

Comical  spinster  falls  asleep  on  park  bench;  nearby  sits  man  accompan- 
ied by  large  dog.  Spinster  dreams  she  is  being  kissed.  Wakes  and  finds  dog 
licking  her  face. 

SCENARIO 

Cast   of   Characters 

Spinster,  burlesque  in  manner  and  attire 

Man,  portly  and  dignified 

Dog,  large  and  shaggy  preferred 

Parlor  Maid 

Several  well  dressed  young  men 


82 


MOTOGRAPHY  15 

Scene  Sets 
Park  with  two  adjacent  seats 
Parlor 

Synopsis 

CHAPTER  I.     Prologue. 

Scene  1.  Park  with  two  adjacent  seats.  Enter  spinster  right,  takes 
nearest  seat.  Enter  man  and  dog  left,  man  takes  remaining  seat,  spinster 
much  disgusted.  Man  falls  asleep.  Spinster  glowers  and  fusses  but  sticks 
to  the  seat  and  finally  shows  drowsiness. 

Title:     "The  Dream." 

Scene  2.  Parlor.  Discovered,  spinster  reading  letter  and  smiling 
much.  Enter  parlor  maid,  announces  caller,  exit  and  return  with  first  young 
man.  Exit  parlor  maid.  Welcome  of  man  by  spinster,  man  begins  to  kiss 
spinster.  Enter  second  young  man  unannounced,  surprise  and  confusion  of 
all;  exit  first  young  man  hastily  in  confusion.  Business  of  love-making  by 
second  young  man  and  spinster,  young  man  begins  to  kiss  spinster.  Enter 
two  more  young  men  unannounced,  surprise  and  confusion.  Enter  more 
j'oung  men,  all  give  excess  attention  to  spinster,  then  begin  talking  among 
themselves  as  if  quarreling  about  spinster;  meanwhile  one  young  man  is  aside 
with  spinster  and  begins  kissing  excessively. 

Title:    "The  Reality." 

Scene  3.  Su7nc  as  Scene  1.  Discovered,  man  on  seat  asleep  and  spin- 
ster on  other  seat  asleep,  dog  licking  spinster's  face.  Spinster  wakes,  horrified, 
belal)ors  dog  with  umbrella  and  then  belabors  man  with  uml^rella.  Exit  dog 
and  man,  left. 

Title:     "But  It  Was  a  Lovely  Dream." 

{Back  to  Scene  S.)  Stage  business  of  rage  by  spinster  looking  off  left, 
then  slowly  subsides,  sits  on  seat,  clasps  hands,  smiles  and  looks  upward  in 
attitude  of  blissful  reverie.     (End  of  Picture.) 

The  reviewing  editor  of  a  motion-picture  manufacturing  com- 
pany proba])ly  would  read  as  far  as  "Dog,"  and  reject  the  manu- 
script. Trained  animals  are  almost  an  impossibility  in  motion- 
picture  production.  It  would  be  necessary  to  find  an  actress  who 
possessed  such  a  dog,  or  an  actor  who  could  make  up  as  a  spinster 
and  who  possessed  a  dog  which  would  lick  its  master's  face.  Aside 
from  this,  there  is  the  method  of  enticing  the  dog  by  food  or  sugar, 
but  this  is  remote  in  probability  of  a  successful  picture. 

SPECIMEN  CHASE  AND  TRICK  SCRIP 

When  trick  pictures  are  written,  the  author  must  keep  his  tricks 
within  the  possibilities  of  the  art.  In  chases,  the  author's  scenes 
must  be  influenced  by  the  opportunities  of  the  producer.  In  the 
following  "scrip" — as  the  written  story  of  a  picture  before  produc- 


83 


16  TflE  MOTION  PICTURE 

tion  is  called — the  title,  plot,  and  scenario  are  given,  and  these 
should  be  followed  by  a  set  of  trick  notes  by  the  author  explaining 
for  the  benefit  of  the  producer  how  the  various  trick  scenes  shall 
be  or  may  be  produced. 

TITLE 
High  Jumping  Johnnie 

PLOT 

Johnnie  is  an  acrobat  out  of  a  job.  Hungry,  he  buys  a  sandwich  but  has 
no  money  to  pay.  The  sandwich  man  chases  him.  He  runs  into  an  apple  cart, 
upsets  it,  and  the  apple  man  chases.  Upsets  stand  of  newsdealer,  who  joins 
chase.  Upsets  baby  carriage,  nurse  joins  chase.  Collides  with  policeman, 
who  joins  chase.  The  chase  now  being  on,  Johnnie  easily  vaults  a  wall,  which 
the  others  require  ladders  to  climb.  In  a  barn-yard,  hay-loft  door  of  barn  is 
8  feet  from  ground.  Johnnie  vaults  in  easily;  others  try,  but  must  enter  by 
door;  when  all  are  in,  Johnnie  jumps  out  of  loft  door  and  flees  dowTi  a  coun- 
try road  toward  a  bridge.  Johnnie  jumps  from  bridge  into  water;  pursuers 
follow;  Johnnie  jumps  back  from  water  onto  bridge;  pursuers  must  climb 
out  over  the  bank.  In  hot  pursuit  down  country  road,  Johnnie  jumps  sheer 
to  the  sky  and  catches  a  passing  airship,  making  final  getaway.  (See  trick 
notes;  practical  airship  not  required.) 

SCENARIO 

Cast  of  Characters 

High-Jumping  Johnnie,  an  acrobat,  must  jump  well,  swim  well,  and  have 

experience  on  the  horizontal  bar 
Double  for  Johnnie,  or  dummy  substitute 
Men,  first  and  second 
Aviator,  and  assistants 
Pursuers,  including  policeman,  nurse,  men,  etc. 

Scene  Sets 

Circus  tent  entrance  or  exterior   (Studio) 

Another  circus  tent  with  entrance  and  sign  (Studio) 

Cloud  canvas  on  rollers.     (See  trick  notes  J  and  L) 

Bedroom   (Studio) 

Office  building  entrance,  with  sign 

City  street  scenes 

Country   scenes 

Bridge  and  water  scene 

Property  List 

Scene  1.     Bed,    table,    chairs,    washstand,    mirror,    comb,    washbowl, 

water  pitcher,  towel,  dumb-bells,  Indian  clubs,  circus  bill. 
Scene  2.     Sign,   packing  box. 
Scene  4.     Sign. 


84 


MOTOGRAPHY  17 

Scene  5.  Park  seat,  sandwich  wagon  with  sandwich  material  com- 
plete, white  apron  and  cap  and  large  fork  for  sandwich  man. 

Scene  6.     Apple  cart  and  apples. 

Scene  7.  Trestles  and  boards  to  be  knocked  off;  newspapers  and 
magazines. 

Scene  8.     Baby  carriage;  dummy  baby;  stripe  uniform  for  nurse. 

Scene  9.     Uniforms  for  two  policemen. 

Scene  10.  Trestle  for  jump  from  fence;  two  or  three  ladders,  say 
six-foot,   eight-foot  and  ten-foot,   one  each. 

Scene  14.  Dummy  for  Johnnie  if  double  is  not  available;  duplicate 
costume  for  double  if  double  is  available. 

Scene  17.     Airship.     (See  trick  notes.) 

Scene  18.     Horizontal   bar. 

Synoj)sis 

CHAPTER  I.       Prologue. 

Scene  1.  Bedroom,  poorly  furnished;  dumb-hells  and  Indian  clubs  on 
floor;  circus  bill  announcing  "High-Jumping  Johnnie"  on  wall.  Discovered, 
Johnnie  washing  face.  Takes  short  turn  with  clubs  or  dumb-bells,  dresses  for 
street,  stage  business  toward  cii'cus  bill  on  wall,  looks  at  watch,  exit  through 
door. 

Title:    "Loses  His  Job." 

Scene  2.  Exterior  of  circus  tent  entrance.  Sign  on  tent,  "Closed  by 
Sheriff."  Discovered,  first  man  sitting  on  packing  box  near  tent  wall,  head 
in  hands.  Enter  Johnnie,  sees  sign,  consternation  at  sign,  taps  man  on  shoul- 
der, asks  about  sign,  man  shakes  head.  Johnnie  indicates  pocket  and  stage 
business  of  asking  whether  anybody  gets  any  pay;  man  shakes  head.  Man 
assumes  disconsolate  pose  again.     Exit  Johnnie,  doleful. 

Scene  3.  Another  ciiTus  tent  entrance.  Enter  Johnnie  at  one  side,  exit 
into  tent;  enter  from  tent  Johnnie  and  second  man;  Johnnie  is  asking  for 
employment,  stage  business  of  showing  that  he  is  an  acrobat;  man  shakes 
head  always  indicating  no  work  for  Johnnie.  Exit  man  into  tent.  Exit 
Johnnie  one  side  after  stage  business  of  disappointment  and  hunger. 

Scene  4.  Office  building  entrance.  Sign  at  door  reads,  "Theater  Agency. 
Vaudeville  Acts  Wanted."  Enter  Johnnie  one  side,  sees  sign,  business  of  joy, 
exit  into  office  building  entrance;  business  of  passers-by;  enter  Johnnie  from 
office  building  entrance,  sorrowfully.  No  work.  Exit  one  side  after  stage 
business  of  hunger. 

CHAPTER  II.     The  Chase,  in  the  city.  • 

Scene  5.  Edge  of  park;  park  seat  left;  red-hot  sandwich  man  and  cart 
at  curb  at  right;  camera  set  to  panoram  from  seat  to  sandwich  cart.  Enter 
Johnnie,  left,  disconsolate.  Hunger,  despondency.  Looks  off  stage  right,  be- 
comes thoughtful,  rises  and  walks  toward  right.  {Panoram  camera  to  follow 
actor.)  Stops  at  sandwich  cart,  talks  with  man,  orders  sandwich;  man  makes 
sandwich  and  hands  to  Johnnie;  Johnnie  takes  bite;  man  asks  for  pay;  Johnnie 
explains;  man  angry;  Johnnie  continues  explaining;  man  threatens;  Johnnie 
runs  with  sandwich;  man  follows  with  apron,  cap,  and  fork;  exit  around 
convenient  street  corner. 

Scene  6.     City  street.     Discovered,  apple  man  and  cart.    Enter  Johnnie 


85 


18  THE  MOTION  PICTURE 

running,  collides  with  cart  and  falls,  but  holds  on  to  sandwich;  scatters  apples 
in  street.  Johnnie  recovers  feet,  picks  up  an  apple,  puts  apple  in  one  pocket 
and  sandwich  in  another  and  runs  off  stage.  Enter  sandwich  man;  exit  sand- 
wich man  and  apple  man  pvu-suing  Johnnie. 

Scene  7.  City  street  corner.  News  stand  and  attendant.  Enter  Johnnie 
running,  collides  with  news  display,  upsetting  it  but  keeps  on  running.  Enter 
pursuers,  business  with  newsdealer,  who  joins  chase.     Exeunt,  running. 

Scene  8.  Residence  street  scene.  Enter  nurse  with  baby  in  carriage. 
Enter  Johnnie  running,  collides  with  carriage,  overturns  carriage  but  keeps 
on  running.  Enter  pursuers.  Exeunt  pursuers  running,  including  nurse, 
baby,   and   carriage. 

Scene  9.  Street  corner  in  residence  district.  Enter  left  up  one  street 
two  policemen.  Enter  right  up  other  street  Johnnie  running.  At  corner, 
Johnnie  collides  with  policemen.  Exit  Johnnie,  running,  left.  Enter  right 
pursuers  running  after  Johnnie,  talk  with  policemen,  exeunt  all  running  left. 

Scene  10.  City  or  suburban  scene  with  wall  8  feet  high.  Enter  Johnnie, 
makes  running  jump  sheer  to  top  of  wall  (Trick  Note  A)  and  down  on  opposite 
side.  Enter  pursuers.  Run  to  wall,  attempt  to  climb  but  all  fail.  Exeunt 
two  or  three  and  enter  again  with  short  ladders,  all  scale  wall  and  vanish  on 
other  side. 

CHAPTER  III.     The  Chase,  in  the  country. 

Scene  11.  Country  with  fence  and  gate.  Discovered,  Johnnie  in  back- 
ground, running  toward  camera,  clears  fence  by  leaping  from  earth  to  top 
of  fence  and  again  to  earth  (Trick  Note  B),  runs  toward  camera,  and  exit. 
Enter  pursuers  who  at  first  try  to  climb  fence  but  discover  gate  and  open  it, 
passing  through  gate  and  toward  camera  and  exeunt  in  pursuit. 

Scene  12.  A  steep  earth  hank  5  feet  high.  (Note  C.)  Enter  Johnnie 
on  top  of  bank,  leaps  to  bottom;  enter  pursuers,  following  and  coming  do^vn 
bank;  exit  Johnnie  on  lower  level;  exeunt  pursuers  following. 

Scene  13.  Similar  to  Scene  It,  adjacent  part  of  same  bank.  Enter 
Johnnie  on  lower  level,  leaps  to  higher  level  (Trick  Note  D)  and  keeps  on 
running.  Exit  Johnnie.  Enter  pursuers,  lose  much  time  in  climbing  to  higher 
level.      Exeunt. 

Scene  14.  A  barnyard  and  barn,  with  doors  at  ground  level  and  loft 
door  about  8  feet  above  ground  level.  Enter  Johnnie  and  leaps  into  open  loft 
door  (Trick  Note  E).  Enter  pursuers  and  try  to  make  loft  door  but  fail. 
Johnnie  takes  sandwich  from  pocket  and  takes  a  bite,  sandwich  man  rages. 
All  pursuers  take  lower  door  to  barn.  When  all  are  in,  Johnnie  jumps  from 
loft  door  and  exit;  pursuers  appear  in  loft  door,  some  falling  through  loft 
door  to  earth  and  others  returning  by  lower  door.     Exeunt.     (Note  F.) 

Scene  15.  A  country  road  with  bridge  in  middle  distance.  Enter  from 
foreground  Johnnie  and  pursuers  very  close  behind,  all  running  toward  bridge. 

Scene  1G.  A'^ear  the  bridge  of  Scene  14-  Bridge  is  at  left;  the  foreground 
is  water  under  and  near  the  bridge;  in  the  middle  ground  is  the  distant  bank  of 
the  river.  Enter  Johnnie,  left,  on  bridge,  closely  pursued.  Johnnie  jumps 
from  bridge  into  water,  pursuers  all  follow.  When  all  are  in  the  water,  Johnnie 
jumps  sheer  from  the  water  to  the  bridge  again  (Trick  Note  G)  and  runs  off 
bridge  left;  pursuers  lose  much  time  climbing  out  of  water  upon  bank  in 
middle  ground  and  exeunt  after  Johnnie. 


86 


MOTOGRAPHY  19 

CHAPTER  IV.     Conclusion. 

Title:     "The  Airship." 

Scene  17.  Open  country,  with  airship  or  aeroplane  on  ground.  Enter 
aviator  and  assistants,  right;  walk  to  airship;  examine  all  parts  carefully; 
aviator  takes  driver's  seat,  assistants  start  propellers  and  exeunt;  airship 
starts  and  passes  off  stage,  right,  rising.     (Trick  Note  H.) 

Scene  18.  Country  road.  Enter  Johnnie  and  pursuers,  from  back- 
ground, running  toward  camera.  All  notice  airship  (off  stage)  and  stop  run- 
ning, looking  up.  Johnnie  makes  sheer  leap  to  sky,  from  extreme  foreground, 
off  stage  through  top  of  picture.  (Trick  Note  I.)  Pursuers  run  forward  and 
off  stage,  always  looking  upward,  showing  amazement  and  chagrin  after 
Johnnie's  leap. 

Title:     "Safety  at  Last." 

Scene  19.  Airship  in  flight  in  foreground,  clouds  in  background.  (Note 
J.)  Johnnie  enters  through  bottom  of  picture,  extreme  foreground,  ;  eizes 
airship  and  climbs  aboard.     (Trick  Note  K.) 

Scene  20.  (Note  L.)  Near  view  of  airship.  Discovered,  Johnnie, 
who  nearly  fills  the  screen.  Takes  sandwich  from  pocket  and  apple  from 
another  and  eats,  with  stage  business  downward  as  if  to  pursuers  on  earth 
below.     (Note  M.) 

Scene  21.  Country  roadside.  Discovered,  all  pursuers  in  state  of 
collapse,  one  or  two  showing  rage  and  gesticulating  toward  sky  toward  Johnnie 
in  airship.     (End  of  picture.) 

The  average  picture-play  editor  would  read  that  "scrip"  only  so 
far  as  the  first  time  he  saw  the  word  "airship,"  were  it  not  that  the 
mention  of  airship  is  coupled  with  the  memorandum,  "See  Trick 
Note." 

TRICK  NOTES 

Trick  Note  A.  The  leap  to  top  of  wall  and  the  entra?ice  may  be  made 
in  one  action  with  reversing  camera.  Johnnie  takes  position  on  top  of  wall, 
back  to  camera;  mark  chalk  line  around  both  feet;  start  reversing  camera; 
Johnnie  stoops,  puts  hands  on  top  of  wall,  leaps  backward  to  earth,  easing  leap 
with  hands  on  wall;  then  runs  backward  off  stage  at  entrance  point.  When  re- 
versed in  the  jyrint,  this  enters  Johnnie  and  carries  him  to  the  top  of  the  wall  in  a 
flying  leap.  To  complete  the  scene,  Johnnie  takes  same  position  on  top  of  wall, 
feet  in  chalk  lines,  and  assumes  as  nearly  as  possible  same  attitude;  start  direct 
camera;  signal  pursuers  on;  pursuers  enter  and  Johnnie  leaps  forward  from 
camera  out  of  sight.  A  platform  beyond  the  wall  may  shorten  the  leap,  which 
should  not  have  the  aid  of  hands.  The  two  actions,  reverse  and  then  direct,  com- 
plete the  scene. 

The  leap  to  top  of  wall  and  the  entrance  may  be  made  in  two  actions.  First 
action:  Johnnie  takes  position  on  top  of  wall,  back  to  camera;  mark  chalk  line 
both  feet;  start  reversing  camera;  Johnnie  stoops,  puts  hands  on  top  of  wall  and 
leaps  backward  to  earth,  easing  leap  with  hands  on  wall;  mark  carefully  around 
feet  and  around  hands  if  hands  touch  earth.  Second  action:  Start  direct  camera 
without  actors;  Johnnie  enters,  runs  to  wall,  and  takes  exact  position  with  feet 
as  marked  in  jump  from  wall,  assuming  as  nearly  as  possible  the  same  attitude 


87 


20  THE  MOTION  PICTURE 

as  when  landing  from  the  wall.  Third  action:  The  scene  from  top  of  wall,  with 
direct  camera,  as  before.  The  three  actions,  direct,  then  reverse,  then  direct,  com- 
plete the  scene. 

The  leap  before  the  reversing  camera  should  he  backward,  not  face  toward 
the  camera,  and  the  effect  of  the  hands  upon  the  wall  is  that  at  the  end  of  the  rise 
they  help  Johnnie  to  gain  the  top  with  his  feet  and  acquire  a  momentary  equilib- 
rium there.  The  scene  in  two  actions  is  preferred  if  Johnnie  is  competent  to 
run  backward  realistically.  If  the  three-action  method  is  adopted,  the  change 
from  the  first  entrance  to  the  reversing  action  may  he  made  either  at  the  point  of 
leaving  the  ground  for  the  leap,  or  a  few  steps  jyrior  to  rising. 

Trick  Note  B.  Saiyie  method  as  for  Trick  Note  A.  Mark  with  chalk 
the  position  of  the  feet  upon  the  top  of  the  fence.  With  Johnnie  "jumped"  into 
the  picture,  running  cdmost  directly  toward  the  camera  and  on  the  distant  side 
of  the  fence,  the  awkwardness  of  running  backward  will  he  obscured  and  less 
running  backward  will  be  required,  so  that  the  two-action  method  should  be 
thoroughly  feasible.  In  the  second  action,  enter  the  pursuers  before  Johnnie 
leaves  the  fence  jumping  down. 

Note  C.  One  side  of  a  railway  cut  ought  to  serve  for  this  scene  set.  A 
water-washed  guUey  or  river  bluff  with  beach  at  bottom  is  suitable. 

Trick  Note  D.  Same  method  as  for  Trick  Note  A.  The  hackivard  leap 
for  safety's  sake,  should  be  squarely  backward  and  not  diagonally  over  the  bank. 
Use  hands  as  before.  Mark  position  of  feet  as  before.  Two-action  method  pre- 
ferred, and  Johnnie  may  be  "jumped"  into  the  picture  if  desired. 

Trick  Note  E.  Sa77ie  method  as  for  Trick  Note  A.  As  it  is  desirable  that 
the  pursuers  shall  enter  as  quickly  after  Johnnie,  the  last  action  of  the  scene  may 
start  with  Johnnie  in  crouching  position  in  loft  door  with  back  to  camera,  the 
pursuers  coming  on  while  he  rises  and  turns  to  face  out  of  the  door. 

Note  F.  Scene  14  fnay  be  staged  in  a  city  house  if  preferred,  selecting 
a  house  with  high  first  floor,  the  windows  being  about  8  feet  from  the  ground. 
Johnnie  jumps  into  an  open  vnndow,  pursuers  rage  under  window,  then  enter 
house  up  .^teps  and  through  front  door,  then  Johnnie  jumps  from  window  and  runs. 

Trick  Note  Q.  Scene  16  may  be  made  according  to  any  one  of  three 
methods,  which  may  be  named  the  double  method,  the  dummy  method,  and  the 
repeater  method.  The  first  is  preferred  if  an  actor  for  Johnnie's  double  is  avail- 
able. 

The  "double"  method  is  so  named  because  it  uses  two  actors  who  are  "doubles," 
looking  so  much  alike  or  made  up  so  much  alike  that  the  audience  does  not  dis- 
tinguish them  one  from  the  other.  As  the  substitute  for  Johnnie  appears  for 
but  a  brief  period  and  is  in  active  motion  all  the  time,  the  resemblance  need  not 
he  exceedingly  accurate.  In  producing  Scene  16  direct  and  reversing  cameras 
are  used.  First  action:  Johnnie's  double  enters  left,  on  bridge,  direct  camera 
running,  and  jumps  from  bridge  into  water,  followed  even  before  diving  by  the 
leaders  of  the  pursuers,  who  plunge  after  him.  Second  action:  When  all  pur- 
suers are  in  the  water,  start  reversing  camera.  Pursuers  make  much  splashing 
but  make  no  progress  in  swimming  forward,  but  anyone  skilled  in  swimming 
huckvmrd  may  do  so.  Enter  the  real  Johnnie  walking  or  running  backivard, 
entering  left  on  bridge  and  walking  backward  to  the  point  of  diving,  diving  back- 
ward if  he  has  sitfficient  skill  in  diving,  a  straight  hackivard  jump,  striking  the 
water  feet  first  being  preferred.    Third  action:  Start  direct  camera.   Pursuers  may 


88 


MOTOGRAPHY  21 

swim  forward  now  and  climb  out  upon  bank  opposite  camera,  thence  running 
across  bridge  and  exeunt  left.  The  actions  are  used  in  the  scene  in  the  order  in 
which  they  are  taken.  In  the  last  action  Johnnie  must  not  be  seen,  even  though 
the  camera  must  be  stopped  to  get  him  out  of  the  picture. 

The  "dummy"  method  requires  a  weighted  dummy  resembling  Johnnie. 
In  the  first  action,  the  real  Johnnie  runs  on  left  and  crouches  upon  the  edge  of 
the  bridge,  simulating  a  leap  as  nearly  as  possible,  but  does  not  go  into  the  water. 
The  camera  is  stopped,  a  dummy  is  substituted,  held  by  a  string  running  off  stage; 
start  the  camera,  release  dummy  by  the  string  and  order  pursuers  on.  The  dummy 
is  weighted  to  sink  when  it  strikes  the  water.  Second  and  third  actions  as  before. 
Poorest  of  the  three  methods. 

The  "repeater"  method  requires  Johnnie  to  dive  twice  and  uses  a  dummy 
as  well,  but  the  dummy  merely  makes  a  splash  and  does  not  appear  in  the  picture, 
so  a  weighted  bag  is  sufficient.  The  first  action  is  in  two  parts.  Johnnie  runs 
on  left  and  dives  from  bridge;  stop  camera;  Johnnie  comes  from  water;  dummy 
is  fixed  to  bridge  to  be  released  to  make  splash  by  pull  of  string  running  off  stage. 
Start  direct  camera,  release  dummy  weight  for  splash,  order  pursuers  on  as  water 
splashes.  Second  and  third  actions  as  before,  the  second  action  being  all  the  better 
because  Johnnie's  clothes  show  wet. 

Trick  Note  H.  Scene  made  in  two  actions,  the  second  action  being  with 
reversing  camera.  Build  a  dummy  aeroplane  after  the  Wright  biplane  model, 
an  easy  type  to  copy  in  dummy.  Arrange  it  to  slide  backward  to  earth  on  a 
pair  or  more  of  inclined  wires.  Must  have  practical  propellers  turning  very 
easily  by  slight  breeze.    Make  second  action  of  scene  before  making  first  action. 

Second  action:  With  reversing  camera.  Enter  airship  with  aviator  in 
driller's  seat,  sliding  backward  down  inclined  wires,  propellers  turning.  Airship 
stops  on  ground,  but  propellers  keep  on  turning;  aviator  takes  tableau  attitude 
to  be  assumed  again  in  first  action. 

First  action:  With  direct  camera.  Discovered,  the  aeroplane  just  as  it 
was  in  tableau  of  second  action,  but  without  aviator  and  with  propellers  stopped. 
Propellers  may  be  tied  to  frame  with  a  light  string  easily  broken.  A  sufficient 
breeze  should  be  blowing  to  turn  the  propellers  continuously  after  they  have  started. 
Enter  aviator  and  assistants,  or  they  may  be  "discovered"  or  "jumped  in."  In- 
spect airship  thoroughly.  Aviator  takes  seat;  assistants  start  propellers  by  turning 
them  forcibly  which  breaks  string  and  breeze  then  keeps  them  turning.  Exeunt 
all  assistants  left.  Aviator  in  driver's  seat  as.sumes  the  tableau  pose  of  the  second 
action,  made  at  the  close  of  the  second  action  in  front  of  the  reversing  camera 
and,  therefore,  appearing  at  the  beginning  of  the  second  action  of  the  scene  in 
reproduction. 

In  lieu  of  (lie  dummy  airship  and  the  staged  action,  a  bona  fide  airship  or 
aeroplane  making  a  bona  fide  start  or  a  view  of  an  airship  in  flight  would  serve 
the  purposes  of  Scene  17.  Stock  actors  need  not  appear  in  the  scene.  One  direct 
action  scene  of  a  bona  fide  airship  under  any  condition  of  motion  would  be  all 
that  the  scene  requires,  the  trick  feature  of  the  start  of  the  dummy  being  entirely 
obviated. 

The  entire  series  of  scenes  involving  the  airship  or  aeroplane  may  be  made 
with  a  free  balloon  instead,  if  the  properties  are  more  easily  available  to  the  pro- 
ducer. Scene  17  is  then  a  bona  fide  scene  of  any  balloon  ascension.  In  Scene  18, 
Johnnie  leaps  to  catch  a  dangling  rope.    Scene  19,  the  basket  of  the  balloon  is  seen 


89 


22  THE  MOTION  PICTURE 

and  Johnnie  enters  by  climbing  the  rope  through  the  bottom  of  the  picture.  Scene 
20  is  staged  in  the  balloon  basket. 

Trick  Note  I.  In  front  of  the  camera  and  as  high  as  Johnnie  can 
jump  and  catch  is  a  fixed  horizontal  bar  such  as  acrobats  use.  The  camera  is  set 
to  take  the  ground  below  the  bar  as  the  foreground  line  of  the  picture  and  to  clear 
a  foot  or  more  between  the  bar  and  the  upper  line  of  the  picture,  the  bar  being  above 
the  picture.  With  a  bar  7  to  8  feet  from  the  ground  and  with  a  3-inch  lens  in  the 
camera,  the  distance  from  camera  to  bar  would  be  about  24  f<^ct.  The  distance 
between  standards  stipporting  the  bar  must  be  more  than  S  feet  that  the  standards 
may  be  out  of  the  picture.  The  shadow  if  any  must  fall  toward  the  camera,  that 
it  may  not  show  in  the  picture.  When  Johnnie  leaps  and  catches  the  bar  he  pulls 
himself  out  of  the  picture  as  rapidly  as  possible,  and  at  that  time  all  eyes  have  been 
fixed  above  the  horizontal  bar,  as  though  the  airship  were  just  there,  and  as  though 
Johnnie  has  jumped  and  caught  the  airship.  If  he  can  get  out  of  the  picture 
quickly  enough,  it  will  seem  that  he  has  jumped  higher  than  the  picture  to  catch 
the    airfihip. 

Trick  Note  J.  The  airship  {dummy  or  bona  fide)  is  rigidly  supported 
by  invisible  wires  or  by  trestles  at  its  ends,  in  the  latter  case  the  camera  being  set 
close  and  the  trestles  being  off  the  sides  of  the  picture.  Flight  is  simulated  by 
painting  clouds  on  a  canvas  band  and  mounting  the  canvas  on  rollers  and  moving 
the  clouds  past  the  ship  as  a  moving  background.  A  slight  panoram  movement 
and  vertical  rocking  movement  of  the  camera  simulates  the  tipping  and  swerving 
of  the  air.ship  in  flight. 

Trick  Note  K.  Johnnie  enters  by  jumping  upward  and  catching  the 
airship  as  an  acrobat  catches  a  horizontcd  bar,  then  climbs  aboard. 

Note  L.  A  near  view  of  the  motionless  airship.  If  the  cloud  curtain 
on  rollers  is  used,  it  may  be  shown  as  a  background,  Scenes  19  and  20  being  com- 
bined. If  roller  cloud  curtain  be  not  available,  the  view  may  be  so  taken  that  no 
motion  is  needed,  Johnnie  and  the  near  parts  of  the  airship  filling  the  screen, 
with  possibly  the  aviator  also  visible.  Use  the  rocking  or  panoram  of  camera 
to  simulate  the  airship's  movement. 

Note  M.  //  bona  fide  airship  is  available,  no  trick  flights  are  required, 
all  pictures  being  made  with  the  airship  at  rest  except  the  bona  fide  start,  or  a  short 
bona  fide  view  of  the  airship  in  flight.  If  stock  negatirie  of  an  airship  in  flight  is 
available,  it  may  be  used  for  Scene  17  and  the  dummy  for  Scenes  19  and  20  may 
be  of  a  design  in  imitation  of  the  airship  of  Scene  17. 

SPECIMEN  TRA\T5L  SCRIP 

As  a  task  for  an  author,  the  writing  of  a  scrip  for  a  travel  pic- 
ture is  not  a  long  nor  a  difficult  task.  It  is  at  most  a  guidance  for 
the  producer.  In  many  cases  the  author's  scrip  may  be  dispensed 
with  altogether,  the  producer  going  into  the  field  equipped  with 
the  camera  only  and  making  photographs  of  whatever  opportunity 
may  offer  in  the  hope  of  piecing  them  together  to  form  an  acceptable 
series.  The  following  scrip  is  a  specimen  which  might  be  given  to 
a  producer  as  his  instruction,  with  liberty  to  omit  any  unduly  diffi- 
cult scene  and  to  add  whatever  scenes  may  be  offered  by  chance. 


90 


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MOTOGRAPHY  23 

TITLE 

A  Trip  Across  Lake  Michigan 

PLOT 

A  trip  beginning  in  Chicago  and  ending  in  South  Haven,  Michigan, 
via  steamer  "Westland,"  showing  something  of  fruit  traffic. 

SCENARIO 

Cast  of  Characters 

None 

Scene  Sets 

None  Special 

Synopsis 

Title:     "Chicago  River." 

Scene  1.  Panorama  from  one  of  the  bridges,  showing  large  passenger 
steamers  at  dock,  showing  particularly  the  Westland,  on  which  the  trip  is  to 
be  made. 

Scene  2.  Tiirning  of  a  bridge  and  passing  through  of  a  large  freight 
boat. 

Scene  3.  Leaving  of  the  little  passenger  boat  on  its  frequent  trips 
down  the  drainage  canal. 

Title:      "Away  for  Vacation  Days." 

Scene  4.     Ticket  window,    people   buying  tickets. 

Scene  5.     Gangplank  of  steamer,  people  going  aboard. 

Title:     "Leaving  the  River." 

Scene  6.  Travel  scene  from  bow  of  boat,  showing  opening  of  Rush 
Street  bridge  to  let  boat  through.  Better  make  this  with  trick  handle,  half 
speed.  Show  also  points  of  interest  on  banks  of  river  and  lighthouse  on  pier 
at  mouth  of  river. 

Title:     "Chicago  Water  Front." 

Scene  7.  Panorama  of  Chicago  water  front.  Make  this  from  the 
outer  breakwater,  two  or  three  camera  stands  if  necessary. 

Title:     "Out  of  Sight  of  Land." 

Scene  8.  Panorama  of  waves,  showing  details  of  boat  structure,  sweep- 
ing the  horizon  rapidly  from  stern  of  boat  to  stem  without  showing  land. 

Title:     "South  Haven,   Michigan,   Breakwater." 

Scene  9.  View  from  bow  of  steamer  as  vessel  approaches  the  mouth 
of  the  river.    Trick  handle  probably. 

Title:     "South  Haven." 

Scene  10.  Panorama  of  South  Haven  water  front.  Make  from  light- 
house at  end  of  pier. 

Title:     "Oh!     There  you  are!" 

Scene  11.  Passengers  disembarking  from  boat.  Greetings  by  friends. 
May  require  some  posing  and  stock  actors. 

Title:     "Off  for  a  Day  on  the  Farm." 

Scene  12.  'Bus,  loaded,  driving  down  village  street,  passengers  waving 
to  camera  man. 


91 


24  THE  MOTION  PICTURE 

Title:     "Peaches." 

Scene  13.  Peach  orchards,  picking  peaches,  packing  in  baskets,  haul- 
ing to  town,  loading  on  steamer  for  Chicago  market.  Grapes,  plums,  anything 
that  can  be  had  of  the  fruit  industry.    Several  scenes. 

Title:     "South   Haven   .\musements." 

Scene  14.  Dance  pavilion,  roller  coaster,  the  little  launch  on  the  river 
loaded  with  passengers.     Several  scenes.     (End  of  picture.) 

The  picture-show  patrons  like  the  dramas  and  comedies  and  as  a 
rule  find  the  travels  tiresome.  They  demand  the  dramas  and  make 
caustic  remarks  about  the  dry  travels.  The  theater  managers  get 
this  sentiment  from  their  patrons  and,  in  turn,  take  it  to  the  film 
exchanges,  refusing  travels  sometimes  when  offered  for  exliibition. 
The  film  exchanges,  in  turn,  carry  this  sentiment  to  the  manufac- 
turers. The  result  is  a  strange  dodge  on  the  part  of  the  film  manu- 
facturers, producing  W'hat  might  be  called  a  travel  and  drama  or 
travel  and  comedy.  It  is  produced  by  combining  something  of  a 
dramatic  or  comic  nature  with  the  scenery  which  is  to  form  the  sub- 
ject for  the  travel  picture. 

SPECDIEX  TRAVEL  AND  COMEDY  SCRIP 
The  following  is  a  specimen  scrip  for  such  a  film  picture: 

TITLE 
Sammy  at  Niagara  Falls 

PLOT 

A  scenic  review  of  Niagara  Falls.  Sammy  takes  a  train  and  arrives  at 
the  Falls.  In  recording  Sammy's  adventures  at  the  Falls  such  scene  sets  are 
chosen  as  to  do  the  falls  completely 

SCENARIO 

Cast  of  Characters 
Sammy,  ordinary  dress  except  a  comical  cap 
Office  help 
Visitors  at  Falls  for  passers-by  business 

Scene  Sets 
Office  scene 

Bedroom,  poorly  furnished 
A  railway  station 

Another  railway  station,  with  sign,  "Niagara  Falls" 
Natural  scenery  at  Niagara  Falls,  New  York 
Synopsis 
Tide:     "Sammy  is  Off  for  a  Vacation." 


92 


MOTOGRAPHY  25 

Scene  1.  Office,  with  Bookkeeper  and  Typewriter  Operator.  Discovered, 
Sammy,  bookkeeper,  stenographer,  other  help.  Sammy  in  great  glee,  talks 
to  all,  serially,  makes  more  confusion  than  headway  with  his  work,  bookkeeper 
hands  him  pay  envelope,  Sammy  tears  open  and  takes  out  money,  waves 
money  in  glee,  gets  hat,  exit,  all  stopping  work  and  waving  adieu. 

Title:     "Where  Shall  I  Spend  My  Vacation?". 

Scene  2.  Bedroom.  Enter  Sartimy,  in  glee,  carrying  newspaper.  Takes 
off  hat  and  coat,  sits,  feet  up,  reads  paper  with  frowns,  suddenly  great  glee, 
holds  up  paper. 

Title:  "Newspaper  Page,  showing  advei'tisement,  railway  to  Niagara 
Falls  and  return  $4.60,  tickets  good  one  week." 

{Buck  to  Scene  2.)  Sammy  throws  down  paper,  takes  hat  and  coat, 
takes  money  from  pocket  and  replaces  it,  exit. 

Scene  3.  Raihvay  station  platform.  Enter  Sammy,  paces  platform 
impatiently;  enter  supes  and  passers-by.  Enter  train,  Sammy  gets  on  board, 
exit  train. 

Scene  4.  Raihvay  station  platform,  with  station  sign  "Niagara  Falls," 
Enter  train.  Enter  passengers  leaving  train,  Sammy  last,  exit  Sammy  one 
side. 

Scene  5.  Panorama  of  the  Falls,  from  any  convenient  elevation,  such 
as  balcony  at  Windsor  Hotel,  Canadian  side. 

Scene  6.  Prospect  Point.  Shows  American  Falls  and  protecting  rail- 
ing at  Prospect  Point.  After  panorama  to  show  scene,  when  scene  is  nearly 
out,  enter  Sammy  with  fish  pole  and  l^egins  to  bait  hook. 

Scene  7.  The  stone  bridge.  "\Miile  panoraming  the  bridge,  Sammy 
nearly  gets  run  over  by  a  rig  while  walking  around  in  the  roadway  with  a  tin 
cup  looking  for  water,  stage  business  of  thirst. 

Scene  8.  Terrapin  Island.  View  from  Goat  Island,  showing  bridge 
to  Terrapin  Island,  panoraming  for  view.  As  view  nears  end,  Sammy  comes 
out  half  way  across  Terrapin  Bridge  with  a  string  on  his  tin  cup,  lowers  the 
cup  into  the  water,  hauls  it  up  and  gets  a  much  satisfying  drink. 

Scene  9.  ^laid  of  the  Mist.  Show  boat  at  dock,  and  passengers  in- 
cluding Sammy  passing  aboard.  Falls  in  background. 

Scene  10.  Camera  on  board  the  Maid  of  the  Mist.  Near  view  of  the 
Falls.  Sammy  appears  at  rail  in  near  foreground  of  camera  and  is  deathly 
seasick. 

Scene  11.  Cave  of  the  Winds.  Panoram  for  view,  then  pick  up  Sammy 
and  panoram  him  half  way  across  the  bridges  between  Goat  Island  and  the 
Cave  of  the  Winds.  He  becomes  afraid  and  turns  back.  Again  attempts  it, 
but  again  turns  back,  this  time  finally.  Camera  keeps  him  in  field  continu- 
ously.      (End  of  Picture.) 

Such  a  combination  enables  the  film  manufacturer  to  render 
his  travel  pictures  more  acceptable  to  that  class  of  patron  disliking 
the  travel  in  its  pure  form.  The  exhibitor  also  has  opportunity  to 
advertise  the  picture  in  his  theater  front  announcement  either  as 
"A  Roaring  Comic"  or  as  "A  Beautiful  and  Wonderful  Nature 
Picture." 


93 


26  THE  MOTION  PICTURE 

SPECIMEN  INDUSTRIAL  SCRIP 

To  depict  an  industry  completely  sometimes  requires  pictures 
taken  in  various  parts  of  the  world.  "The  Rubber  Industry"  should 
begin  with  views  of  the  tropical  rubber  trees,  curing  the  sap  for 
shipment  and  loading  on  vessels.  Then  the  scene  shifts  to  the  northern 
factory,  the  processes  of  bringing  the  rubber  into  commercial  shape 
and  the  manufacture  of  some  well  known  article  wholly  or  largely 
composed  of  rubber.  The  picture  may  close  with  a  scene  showing 
manufactured  article  in  use.  The  scenes  taken  inside  the  factory 
doubtless  would  require  artificial  lighting. 

An  industrial  film  well  done  sometimes  involves  scenes  of  great 
difficulty,  and  even  trick  pictures.  The  following  specimen  scrip 
calls  for  the  "stop"  picture. 

TITLE 

Raising  Watermelons 

PLOT 

Preparing  the  ground  and  planting.  Then  a  growing  vine  by  stop  pic- 
ture. Picking,  loading,  hauling,  loading  cars,  freight  train  in  transit  to  city, 
melons  on  sale  in  city  store  front. 

SCENARIO 

Title:     "Preparing  the  Ground." 

Scene  1.  (Select  a  scene  with  picturesque  background,  showing  gate 
from  field  to  highway.  Take  camera  stand  to  panoram  field,  gate  and  high- 
way, including  background  objects.  Build  permanent  camera  stand,  that  the 
identical  position  of  camera  may  be  taken  from  time  to  time.)  Plowing  and 
fertilizing  in  the  fall. 

Scene  2.     From  same   viewpoint,   a  snowstorm  scene. 

Scene  3.     From  same  viewpoint,  a  sleigh  passing  on  the  highway. 

Title:     "In  the  Spring,  the  Work  Begins  Again." 

Scene  4.     From  same   viewpoint,   spring  plowing. 

Scene  5.     Forming  the  hills  for  planting. 

Scene  6.     Planting  the   seed. 

TitU:    "The  Growing  Plant." 

Scene  7.  Stop  picture,  studio.  The  hand  planting  the  seed,  the 
breaking  of  the  plant  through  surface  of  earth,  growing  hourly  to  blossom. 

Scene  8.     Stop  picture  of  field. 

Scene  9.     Stop  picture  of  near  view  of  melon. 

Title:     "Selecting  the  Ripe  Fruit." 

Scene  10.  View  of  field  with  man  working,  testing  melons  for  ripeness. 
As  he  comes  near  the  camera,  his  tests  are  clearly  seen,  and  the  cutting  of  the 
stem  and  turning  up  of  the  white  side  is  shown. 


94 


MOTOGRAPHY  27 

Title:     "On  the  Way  to  Market." 

Scene  11.     Wagon  in  field,  loading  the  selected  melons. 

ScEisfE  12.     Panoram  loaded  wagon  through   gate  and  along  highway. 

Scene  13.     Near  shipping  point,  many  wagons,  all  loaded. 

Scene  14.  Loading  the  melons  into  railway  cars,  showing  method  of 
handling. 

Scene  15.  The  melon  farmer  gets  the  money  at  the  car  door  from  the 
shipper. 

Scene  16.  From  the  caboose  of  a  railway  freight  train,  showing  train 
ahead  and  scenery  passing  by,  running  through  rural  district. 

Scene  17.     Same,   entering  large  city. 

Scene  18.  City  store  front,  melons  on  sale.  Lady  enters  and  buys. 
Delivery  boy  puts  purchased  melon  in  basket  and  exit  carrying.  (End  of 
Picture.) 

Who  is  the  Author.  Usually,  it  is  the  producer.  Surely  no 
author  is  better  qualified  to  write  within  the  limitations  of  the  motion- 
picture  art  than  the  producer.  Surely  no  producer  is  better  able 
to  interpret  a  story  than  the  author.  In  industrials,  the  producer 
may  look  over  the  situation  in  the  capacity  of  author  and  write  the 
scrip  in  memorandum  form  as  his  field  notes  for  working  with  the 
camera.  With  the  notes  in  hand,  he  takes  the  camera  man  and 
equipment  and  makes  the  various  scenes  which  his  notes  show  pos- 
sible or  desirable.  In  travels,  comedy,  or.  dramatic  accompaniment, 
the  field  should  be  looked  over  to  leam  its  possibilities,  and  no  one 
is  better  qualified  than  an  experienced  producer.  In  current  events, 
an  experienced  producer  is  the  best  judge  of  advantageous  view- 
points. In  chases,  the  central  idea,  the  joke  of  the  picture,  may  be 
sufficient  information  to  pass  from  the  author  to  the  producer,  the 
producer  providing  scenes  to  embody  the  thought  in  a  picture 
within  the  limitations  of  the  art  and  his  immediate  environment. 
It  is  in  comedies  and  dramas  that  the  author  as  such  may  be  entirely 
remote  from  the  producer.  Scrips  for  comedy  and  drama  may  be 
written  as  short  stories  are  written,  and  may  be  submitted  to  film 
manufacturers  as  short  stories  are  submitted  to  magazine  publishers. 

THE  PRODUCER 

The  producer  is  in  charge  of  the  studio,  of  the  scene  painters, 
of  the  sign  writers,  of  the  stage  carpenters,  of  the  property  man,  of 
the  actors,  and  is  nominally  in  charge  of  the  camera  men. 

When  the  producer  undertakes  a  picture,  the  scrip  is  made 
as  complete  as  he  desires  by  adding  details  of  scenes,  notes  of  probable 


95 


28  THE  MOTION  PICTURE 

location  of  outdoor  scenes,  names  of  actors  suitable  for  the  parts  or 
notes  on  actors  required  to  be  found  for  the  parts,  as  well  as  notes 
on  other  pictures  being;  produced  or  to  be  produced  contemporane- 
ously with  the  scrip  being  studied.  Studio  stage  sets  and  scenery 
recjuired  are  noted  and  a  property  list  is  made.  The  titles  also  are 
noted,  for  title  making  is  a  part  of  the  work  quite  distinct  from  scene 
making. 

The  producer  keeps  all  his  departments  running  as  smoothly 
as  possible,  the  motion  scenes  for  a  drama  being  produced  this  week 
while  titles  are  being  made  for  another  drama  for  which  the  motion 
scenes  were  produced  last  week,  and  the  stage  carpenters  and  scene 
painters  are  at  work  upon  studio  settings  and  properties  for  still 
another  drama  for  which  the  motion  scenes  will  be  produced  in  the 
weeks  following. 

The  order  of  producing  drama  is:  (1)  Painting  the  scenery 
for  the  studio  sets,  for  none  but  the  simplest  scene  sets  are  used 
repeatedly.  (2)  Getting  the  properties  and  costumes.  (3)  Getting 
the  actors  and  rehearsing  and  photographing  the  motion  scenes. 
(4)  Producing  the  motion  scenes  before  the  camera.  (5)  Inspect- 
ing the  proofs  of  the  motion  scenes,  retaking  unsatisfactory  scenes 
and  making  additional  scenes  which  may  seem  desirable — some- 
times, alas,  only  for  "padding" — ^after  the  author's  scenes  have 
been  reviewed.  (G)  Rewriting  the  scrip  if  necessary  to  fit  the 
drama  as  embodied  in  the  motion  scenes.  (7)  Writing  the  titles 
finally  and  in  detail.  (8)  Making  the  titles.  (9)  Adjusting  lengths 
of  titles  and  scenes  to  make  the  desired  total  picture  length. 

Studio  Scenes.  The  scenerv  used  for  setting  the  stage  diflFers 
from  the  scenery  of  the  dramatic  stage  by  the  absence  of  color. 
Plain  black  and  white  and  neutral  tints  are  most  desirable,  for  color 
is  objectionable  in  that  it  may  be  misleading  in  tone  values  when 
photographed.  The'scenery  required  is  only  sufficient  to  fill  the  field 
of  the  camera.  Usually  when  staging  an  interior,  but  two  walls  of 
a  room  are  shown.  In  such  a  case,  the  third  wall  is  not  needed  in 
the  scene  set,  nor  arc  flies  needed  for  the  ceiling.  Wall  scenery  may 
be  made  in  sections  or  panels.  Fig.  2,  and  the  sections  may  be  set 
together  as  desired,  making  possible  the  use  of  the  same  painted 
work  for  several  scene  sets  sufficiently  different  from  each  other. 
If  a  spectator  should  recognize  any  scene  as  being  familiar  because 


96 


MOTOGRAPHY 


29 


97 


30 


THE  MOTION  PICTURE 


of  prior  appearance  in  other  dramas,  the  first  thought  would  be 
that  the  film  then  being  viewed  is  an  old  one.  To  avoid  this,  strik- 
ing scenes  and  highly  special  scenes,  Fig.  3,  are  used  but  once.  Only 
the  more  ordinar}-  and  characterless  scenery  may  be  used  repeatedly. 
In  Fig.  2,  which  is  a  good  example  of  scenery  for  repeated  use,  five 
"flats,"  each  so  small  that  they  resemble  the  "wings"  of  a  dramatic 
stage  setting  and  each  only  sufficient  in  height  to  cover  the  film  win- 
dow in  the  image  in  the  camera,  are  shown  combined  for  a  scene 


Fig.  3.     View  of  Indoor  Studio,  with  Stage  Setting  for  Outdoor  Scene 

set.  When  rearranged  with  the  door  at  right  or  at  middle  back,  new 
and  sufficiently  different  sets  are  produced  for  use  in  another  drama, 
while  with  the  addition  of  a  flat  having  a  window,  still  further  com- 
binations may  be  made  to  use  the  scenery  to  its  limit  before  re- 
painting. 

A  set  of  scenery-  flats  so  designed  as  to  be  papered  with  wall 
paper  may  be  changed  beyond  recognition  in  a  few  minutes  and 
at  a  very  small  expense  merely  by  giving  them  a  new  dress  of  figured 
paper.  For  wall  paper,  the  flats  should  have  a  width  proper  to  take 
exactly  two  or  more  full  width  strips  of  wall  paper,  and  the  paper 
should  be  applied  so  that  the  figures  will  match  at  the  edges  when 
the  flats  are  set  together.    Otherwise,  the  effect  is  ludicrous. 


98 


MOTOGRAPHY 


31 


99 


32 


TtiE  MOTION  PICTURE 


In  addition  to  painted  scenery  for  the  studio,  which  may  rep- 
resent either  an  interior  or  an  exterior  scene,  painted  scenery  some- 
times is  used  for  outdoor  staging.  Fig.  4  shows  a  scene  set  from  a 
production  of  "Richard  III/'  made  by  the  Vitagraph  Company. 
The  camera  stands  in  the  foreground  of  the  ilkistration,  facing  the 
scene  set.  The  field  of  the  image  in  the  camera  does  not  extend  to 
the  right  and  left  beyond  the  painted  scenery  representing  the  stone 
wall,  hence  in  the  motion  picture  there  is  given  the  effect  of  an  in- 
definite stone  wall  having  the  arched  entrance.     Behind  the  arch  is 


Fig.  5.     Natural  Scene  Setting,  Outside  of  Cottage 

a  flat  scene  with  houses  and  clear  sky.  This  is  a  painted  scene  also, 
placed  against  the  tight  board  fence  which  runs  across  the  view  at 
the  foot  of  the  railway  embankment.  Beyond  the  railway  embank- 
ment are  trees,  the  tops  of  which  appear  above  the  painted  stone 
wall.  In  Fig.  2  and  Fig.  3,  the  image  in  the  camera  does  not  extend 
above  the  top  of  the  painted  scenery;  in  Fig.  4  the  camera  includes 
the  top  of  the  wall  and  a  strip  of  the  sky  above,  an  effect  which  in 
the  studio  would  recjuire  a  strip  of  sky  scenery  above  and  behind 
the  wall.  The  setting  of  Fig.  4  is  properly  called  a  studio  set,  even 
though  not  staged  inside  a  building.    Fig.  5  shows  a  natural  scene  set. 


100 


I 


i 


MOTOGRAPHY 


33 


Studio  Lighting.  Artificial.  Artificial  lighting  for  studio  scenes 
is  most  economically  done  with  mercury-vapor  lamps.  These  lamps 
are  made  of  long  glass  tubes  containing  mercury.  When  glowing, 
they  gi\e  a  green  light,  rather  disagreeable  to  the  eye  at  first,  but 
very  powerful  in  acting  upon  the  sensitive  photographic  film.  The 
light  must  be  sufficient  to  impress  the  image  upon  the  sensitive  film 
in  the  short  time  allotted  by  the  camera  for  each  of  the  little  pictures. 
This  is  a  minimum  requirement  of  fifty  standard  mercury-vapor 
lamps  for  a  stage  set  measuring  14  feet  wide,  for  satisfactory  results 


Fig.  6.     Indoor  Studio  Setting  for  Outdoor  Scene,  Showing  Lamp  Arrangement  for 

Artificial  Lighting 

in  the  finished  pictures.     Studio  lamp  plants  vary  from  fifty  to  one 
hundred  and  fifty  lamps,  and  vary  in  cost  from  $2,500  to  J^10,000. 

As  used  in  motion-picture  studios,  the  mercury-vapor  lamps 
are  mounted  in  groups,  usually  six  or  more  lamps  per  group,  some 
of  the  lamps  being  hung  from  the  ceiling  of  the  studio  for  top  lights 
and  some  beinff  mounted  in  standing  frames  for  side  lights.  The 
lighting  arrangement  will  be  clear  from  a  study  of  Fig.  6.  The 
studio  is  entirely  without  light  other  than  the  artificial  light  of  the 
mercury-vapor  lamps,  which  are  arranged  upon  the  ceiling  and  upon 
both  sides  of  the  scene  set.     In  a  studio  of  this  kind,  it  is  possible  to 


101 


\ 


34 


THE  MOTION  PICTURE 


confine  all  scenes  to  the  standard  stage  dimensions  of  the  studio, 
the  lamps  being  properly  arranged  and  sufficient  in  number  to  light 
that  standard  stage  area  properly.  Working  with  a  studio  of  the 
type  illustrated  in  Fig.  6  makes  the  producer  entirely  independent 
of  the  weather  conditions  for  his  indoor  scenes.  In  Figs.  2  and  3, 
large  windows  are  placed  in  the  wall  of  the  studio  at  the  left,  making 
possible  photography  by  dayhght  when  the  weather  is  favorable, 
the  daylight  being  supplemented  as  desired  by  the  artificial  light. 
In  Fig.  2,  a  bank  of  mercury-vapor  lamps  is  suspended  from  the 
ceiling,  and  the  side  lights  also  are  in  position.    In  Fig.  3,  a  battery 


Fig.  7.     Lubin  Factory,  Showing  the  Glass-Roof  Studio 

of  top  and  side  lights  are  glowing,  although  the  daylight  window  is 
visible  at  the  left  in  the  view. 

Daylight.  There  is  a  quahty  in  the  best  daylight  picture  which 
is  lacking  in  the  best  picture  made  by  artificial  light.  The  artificial 
lighting  as  used  commercially  is  sufficient  to  impress  the  image  upon 
the  photographic  film,  but  it  does  not  reproduce  in  all  fidelity  the 
strength  and  diffusion  of  daylight,  nor  the  uniformity  in  intensity 
and  direction  throughout  the  whole  scene  which  is  obtained  from 
daylight.  Lighting  a  large  stage  artificially  also  involves  a  large 
expense. 

The  daylight  studio  is  of  three  types — the  glass  house,  the 
turntable,  and  the  yard.  The  c/las.s  house  ii/pe  of  studio  is  shown 
in  external  view  in  Fig.  7.  That  an  auxiliary  lighting  plant  is  de- 
sirable is  evidenced  by  the  details  of  Figs.  2  and  3. 


102 


MOTOGRAPHY 


35 


A  studio  of  the  turntable  type  is  shown  in  Fig,  8.  The  mov- 
able platform  is  turned  to  get  the  sunlight  in  the  right  direction. 
Pictures  may  be  made  with  this  platform  from  early  morning  until 
sunset,  and  the  producer  may  have  his  hght  from  the  desired  direc- 
tion at  all  times.  The  exposure  to  rain  and  wind  are  the  objection- 
able features  of  a  studio  of  this  type.  It  seems  hardly  natural  for 
the  draperies  inside  a  house  to  be  in  motion,  even  in  a  motion  picture. 
Unless  an  inside  studio  also  is  available,  the  producer  is  dependent 
upon  the  weather  in  more  ways  than  sunlight  alone. 

The  yard  studio  is  a  matter  of  setting  up  the  scenery  in  a  fenced 
enclosure,  as  in  Fig.  4.     Where  the  indoor  studio  is  limited  in  size, 


Fig.  8.     The  Vitagraph  Roof  Studio,  Showing  Turntable  Construction 

the  method  of  Fig.  4  may  be  adopted  for  scene  sets  which  cannot 
be  staged  in  the  restricted  space.  One  adjunct  usually  forming  a 
part  of  an  established  yard  studio  is  the  tank.  The  possibility  of 
staging  a  scene  with  even  a  hmited  amount  of  water  adds  much  to 
the  producer's  possibilities. 

Pictures  Without  Studios.  A  prominent  film  manufacturing 
company  operated  for  years  without  a  studio  and  without  painted 
scene  sets,  releasing  a  reel  each  week.  On  several  occasions,  film 
manufacturing  companies,  whose  studios  and  factories  are  located 
in  the  northern  latitudes,  have  sent  producing  companies  to  the 
tropics  in  the  winter,  where  many  complete  dramas  have  been  pro- 
duced before  the  camera  without  studio  and  without  artificial  scenery. 

The  beauty  and  attractiveness  of  a  motion  picture  is  enhanced 
by  avoiding  painted  scenery  and  its  artificial  appearance  whenever 


103 


36  THE  MOTION  PICTURE 

possible.  No  painted  scenery  can  equal  the  detail  and  accuracy 
of  the  physical  objects.  Fig.  3  would  be  more  pleasing  had  the 
camera  and  actors  been  carried  to  Spain  for  a  natural  scene  setting 
adapted  to  the  requirements  of  the  story. 

It  is  the  custom  to  stage  indoor  scenes  in  the  studio  with  painted 
scenery;  to  stage  street  scenes  outdoors  in  the  streets,  using  the 
natural  street  scenes;  and  to  stage  rural  scenes  in  the  country.  A 
studio  set  for  a  street  scene  may  be  made  thoroughly  acceptable  by 
care  in  preparation  of  the  scenery  and  by  avoiding  vegetation  in  the 
scenery.  In  a  street  scene  of  long  duration,  the  studio  setting  is  a 
decided  advantage,  since  the  passers-by  do  not  have  to  be  contended 
with. 

The  selection  of  natural  settings  is  a  feature  of  his  work  by 
which  one  producer  easily  may  excel  another  in  the  quahty  of  his 
product.  The  motion -picture  camera  has  a  "narrow  angle"  eye, 
permitting  the  use  of  a  small  scenic  setting  without  including  the 
whole  country-side  as  a  part  of  the  view.  On  the  contrary,  by  a 
change  of  lenses  in  the  camera,  just  as  much  of  the  whole  view  as 
IS  desired  may  be  included,  panoraming  the  camera  if  necessary 
to  include  still  more.  The  adaptabihty  of  the  setting  to  the  story 
is  the  principal  point  to  be  borne  in  mind  when  selecting  natural 
scene  settings.  Pictorial  merit  in  the  scene  itself  is  of  secondary 
importance,  but  still  is  a  matter  of  much  importance  when  the  best 
of  motion  pictures  are  desired. 

In  outdoor  settings,  whether  wholly  natural  or  wholly  or  partly 
staged  with  painted  scenery,  constant  care  must  be  taken  to  avoid 
incongruous  features  of  the  background  from  appearing  in  the  pic- 
ture. A  scene  which  by  the  story  of  the  drama  is  set  in  the  fastnesses 
of  a  moimtain  range,  far  from  any  civilization,  when  staged  in  a 
ravine  near  the  studio  should  not  show  a  house  gable  in  the  remote 
distance.  The  scene  set  in  Fig.  4,  as  viewed  by  the  fixed  camera 
which  made  the  illustration,  shows  tree  tops  above  the  stone  wall, 
yet  the  tree  trunks  do  not  appear  through  the  arch  of  the  wall.  This 
would  be  an  error  if  it  were  to  appear  so  in  the  finished  motion 
picture.  The  motion  camera  in  the  illustration  is  nearer  to  the 
scenic  stone  wall,  thus  by  its  different  perspective  and  narrower  lens 
angle  placing  the  top  of  the  wall  higher  in  the  sky  and  above  the 
tree  tops,  so  that  the  tree  tops  are  not  seen  in  the  motion  picture. 


104 


MOTOGRAPHY  -37 

Properties  and  Costumes.  The  articles  or  "stage  properties" 
used  by  the  actors,  include  furniture  and  all  kinds  and  classes  of 
house  furnishings  from  parlor  clock  to  cook  stove  for  indoor  house 
scenes  set  in  the  studio;  desks  and  typewriters  for  office  scenes; 
carriages  for  street  scenes;  and  revolvers  and  black  masks  for  the 
bandits  in  the  mountains.  To  obtain  the  articles  needed  for  the 
production  of  a  reel  of  film  each  week  is  a  task  requiring  one  man's 
attention.  Once  used,  such  articles  as  are  likely  to  be  used  again 
are  stored  in  the  "property  room."  Unless  the  property  man  is 
systematic  by  nature,  the  property  room  soon  will  look  like  a  junk 
shop.  Costumes  aside  from  the  ordinary  street  dress  of  the  actors 
also  will  be  found  in  the  property  room,  including  particularly  uni- 
forms for  policemen  and  messenger  boys,  caps  and  aprons  for  the 
parlor  maids,  and  freak  clothing  for  the  comedian.  The  property 
man  is  the  producer's  assistant.  Seamstresses,  tailors,  carpenters, 
and  local  storekeepers  are  in  turn  the  assistants  to  the  property  man. 

Actors.  The  best  source  for  obtaining  actors  is  the  dramatic 
employment  agency.  Experienced  actors  are  desirable,  even  for  the 
minor  parts,  for  the  producer  as  a  rule  has  no  time  for  training  the 
amateur.  The  custom  is  to  employ  actors  for  a  day  at  a  time  only, 
the  standard  price  being  five  dollars  per  day.  One  day  the  pro- 
ducer may  need  three  or  four  actors,  the  next  day  twenty.  In  pro- 
ducing a  drama  occupying  the  producer  for  a  week,  he  may  require 
the  leading  characters  for  four  days  of  work,  a  few  minor  characters 
for  two  days  (one  day  in  the  studio  and  one  day  in  the  field)  and  a 
dozen  more  actors  may  be  needed  for  a  single  scene  requiring,  with 
all  rehearsals,  but  an  hour  or  two. 

Stock  Companies.  Some  actors  seem  to  have  an  inborn  faculty 
for  expressing  thought  without  words,  others  cannot  catch  the  trick. 
The  producer  quickly  recognizes  this  pantomime  ability  in  an  actor 
employed  by  chance,  and  lists  such  an  actor  for  service  in  the  more 
important  characters  of  his  productions,  even  placing  a  few  such 
actors  upon  a  fixed  weekly  or  monthly  pay  instead  of  employing 
them  at  the  day  rate  with  irregular  service.  The  group  of  actors 
thus  employed  continuously  is  called  a  stock  company  and  is  supple- 
mented by  as  many  more  actors  for  a  day  or  more  as  may  be  needed 
for  any  picture.  To  distinguish  between  the  stock  actor  and  the 
transient,  the  latter  is  called  a  swpe,  an  abbreviation  for  supernumerary. 


105 


38  THE  MOTION  PICTURE 

Starring  an  Actor.  For  general  production  of  pictures,  con- 
tinuous use  of  an  actor  in  all  pictures  becomes  objectionable  to  an 
audience.  Most  emphatically  is  this  so  when  in  two  half-reel  pic- 
tures the  same  actor  takes  part  in  the  two  reels  The  young  wife 
who  just  fainted  in  her  husband's  arms  at  the  bedside  of  her  dead 
child  appears  on  the  same  picture  screen  after  a  quarter-minute 
title  as  giddy  sixteen  flirting  with  half  a  dozen  beaux.  On  the  dramatic 
stage,  such  use  of  an  actor  is  not  objectionable,  but  motion  pictures, 
from  the  fact  that  the  scene  sets  are  so  realistic,  lead  the  spectator 
to  accept  the  actors  also  as  real  and  thus  add  another  to  the  burdens 
of  the  producer. 

On  the  other  hand,  an  actor  may  be  "starred"  in  motion  pictures 
as  upon  the  dramatic  stage.  His  name  in  the  picture  title  will  in- 
troduce him  to  the  audience,  and  when  his  name  is  seen  again  in  a 
title  the  same  actor  will  be  expected.  If  "Sammy  at  Niagara  Falls" 
is  successful  on  Sammy's  part,  the  spectator  will  be  pleased  to  see 
another  title  reading,  "Sammy  at  Saratoga,"  "Sammy  Inherits  a 
Fortune,"  "Sammy  Captures  a  Burglar,"  or  "Sammy's  First  Love 
Affair." 

Rehearsals.  In  the  case  of  scenes  set  in  the  studio,  it  is  most 
convenient  to  set  the  stage  complete  and  to  set  the  camera  also  in 
readiness.  The  rehearsal  then  is  made  in  full  dress  upon  the  fully 
set  stage,  and  when  the  scene  is  creditably  performed  the  camera 
is  started  and  the  scene  repeated.  If  the  scene  is  difficult  to  repro- 
duce, two  negatives  should  be  taken.  If  any  flaw  in  the  action  occurs, 
or  if  the  producer  thinks  that  some  variation  would  improve  the 
scene,  the  scene  should  be  retaken,  the  two  scenes  then  being  viewed 
and  the  best  selected  when  criticising  the  proof  copy  of  the  film. 
On  a  scene  of  one  minute  in  duration,  the  cost  of  repeating  for  the 
second  negative  is  only  two  dollars  for  negative  film,  the  stage  set 
and  properties  being  of  course  already  at  hand  and  the  actors  al- 
ready rehearsed. 

In  the  case  of  scenes  set  in  natural  settings,  many  parts  of  the 
action  of  the  leading  characters  may  be  rehearsed  before  going  into 
the  field.  Such  rehearsals  will  shorten  the  time  required  in  the  field, 
and  as  weather  conditions  sometimes  change  suddenly,  the  saving 
of  time  is  well  worth  considering. 

In  the  street  scenes  where  a  citv  or  villajje  street  is  used,  the 


106 


SCENE  FROM  PHOTOPLAY,  "THE  TEMPTRESS" 

Courtesy  of  Independent  Moving  Pictures  Co.,  New  York 


THE  CONTEMPLATED   SUICIDE  PREVENTED  BY  THE  BURGLARS 

Scene  from  Photoplay,  "A  Good  Turn" 
Courtesy  of  Lubin  Manufacturing  Company,  Philadelphia 


MOTOGRAPHY 


39 


action  required  should  be  thoroughly  understood  by  all  actors  in- 
volved, and  completely  rehearsed  if  of  a  nature  to  make  rehearsals 
possible,  Fig.  9.  Any  rehearsal  in  the  street  will  gather  a  crowd  of 
onlookers,  and  the  longer  the  rehearsal  the  larger  the  crowd.  Even 
the  setting  up  of  the  motion-picture  camera  on  its  tripod  is  in  itself 
an  invitation  for  a  crowd  to  gather  around  it,  and  some  of  them  will 
persist  in  trying  to  get  into  the  view.  The  passing  policeman  usually 
will  help,  but  the  scenes,  if  any,  must  be  short  on  a  busy  street. 
City  ordinances  usually  prohibit  the  making  of  "commercial"  motion 


Fig.  9.     An  Indoor  Eehearsal  for  an  Outdoor  Scene 

pictures  in  parks  or  boulevards.     A  bhnd  camera,  in  a  wagon  which 

may  be  stopped  at  the  curb  unobtrusively,  and  two  or  three  actors 

fully  rehearsed,  may  "put  on"  a  street  scene  completely  and  have  it 

photographed  and  finished  before  passers-by  realize  what  is  being 

done,  or  even  without  their  knowledge  at  all,  even  utilizing  some  of 

the  street  traffic  as  a  part  of  the  scene. 

Producing  a   Drama.     To  produce   the  drama,   "A   Midnight 

Cupid,"   the  scrip  of  which  has   been  given,   the  producer  would 

classify  his  scenes  into  "studio"  and  "field"  work,  as  follows: 

Studio  Scenes:     CM  room,  Scenes  2,  3,  5,  7,  26.      Parlor,  Scene  4.    Cot- 
tage bedroom,  Scenes  19,  21,  24. 


107 


40  THE  MOTION  PICTURE 

Field  Scenes:  First  park  set,  Scene  1.  Second  park  set,  Scenes  6,  16. 
Store  set,  Scenes  8,  14,  17.  Cottage  set.  Scenes  9,  10,  15,  18,  23,  25.  Field 
set.  Scenes  11,  12.     Street  set,  Scenes  13,  20,  22. 

Reviewing  these  for  characters,  the  four  principal  characters 
and  three  men  for  minor  parts  will  make  all  field  work  with  the 
addition  of  "children  playing  in  extreme  background"  in  Scene  14, 
and  Scene  6,  which  recjuires  the  two  servants  from  the  studio  scenes; 
the  farmers  cannot  double  for  the  servants  because  they  appear 
together  in  Scene  26. 

Motion  Scenes.  Scene  4  rec|uires  a  bunch  of  troublesome  actresses 
and  a  large  expense  for  wages  for  a  single  scene;  if  possible,  it  should 
be  made  when  the  bunch  of  girls  are  in  the  studio  in  conjunction 
with  the  scenes  of  another  drama.  By  working  this  Scene  4  into 
the  routine  of  another  production  having  a  parlor  scene  with  the 
same  scene  set  and  actresses,  the  expense  will  be  reduced  and  the 
producer's  time  will  be  economized. 

Aside  from  Scene  4,  all  scenes  should  be  made  in  continuous 
work.  The  studio  being  set  for  the  club  man's  rooms.  Scene  26 
may  be  made  first.  This  scene  being  made,  the  actress  who  played 
"woman  aged  40"  and  the  actor  who  played  the  "minister"  is  dis- 
missed. The  two  "well-dressed  men"  may  be  dismissed,  or  they 
may  make  up  promptly  for  grocer  and  policeman  if  the  producer 
desires  them  to  double  in  the  drama.  Time  is  allowed  for  them  to 
make  up  for  the  new  parts  while  Scenes  2,  3,  5  and  7  are  being  en- 
acted before  the  camera  with  the  same  stage  setting  used  for  Scene  26. 

Studio  work  for  the  drama  now  will  be  completed  by  resetting 
the  stage  for  the  cottage  bedroom.  Scenes  19,  21,  and  24,  the  actors 
required  being  only  the  three  leading  characters,  CM,  G,  and  GF. 
These  three  scenes  may  be  made  before  Scene  26,  or  after  return 
to  the  studio  from  the  field  work,  according  to  the  producer's  con- 
venience. 

The  producer  now  takes  into  the  field  the  four  major  actors, 
a  policeman,  two  servants,  two  farmers,  the  grocer,  and  children  for 
Scene  14.  Scene  6  is  rehearsed  and  performed  before  the  camera; 
the  two  actors  taking  the  part  of  servants  are  then  dismissed.  Scene 
16  follows  Scene  6  without  permitting  the  tramp  to  rise  from  his 
position  on  the  bench,  the  action  of  the  two  scenes  being  substan- 
tially continuous,  but  the  camera  lens  being  capped  for  a  foot  of 


108 


i 


MOTOGRAPHY  41 

the  film  to  make  a  break  in  the  negative  between  the  two  scenes 
when  the  negative  is  developed. 

With  a  slight  change  in  camera  stand,  Scene  1  is  produced,  and 
the  actor  taking  the  part  of  the  pohceman  may  be  dismissed. 

Proceeding  to  the  village  where  the  natural  scene  settings  have 
been  selected  or  are  known  beforehand  to  exist,  the  outside  of  the 
village  store  is  taken  first,  Scenes  8,  14,  and  17  being  produced  in 
order.  The  children  now  may  be  dismissed.  The  street  set  may  be 
made  next,  making  Scenes  13,  20,  and  22  in  order.  Next  the  cottage 
set,  making  in  order  Scenes  9,  10,  15,  18,  23,  and  25.  Then  the  field 
set  for  Scenes  11  and  12  completes  the  action  scenes  of  the  drama. 
The  scenes  have  been  made  in  this  order:  4,  26,  2,  3,  5,  7,  19,  21, 
24,  6,  16,  1,  8,  14,  17,  13,  20,  22,  9,  10,  15,  IS,  23,  25,  11,  12.  The 
titles  are  yet  to  produce. 

Revinv  and  Criticism.  When  the  negatives  have  been  developed, 
a  print  is  made  from  each  and  all  are  spHced  together  in  the  order 
in  which  the  scenes  occur  in  the  drama.  The  complete  drama,  in 
action  scenes  only,  is  projected  for  the  criticism  of  the  producer  and 
others,  including  perhaps  the  author.  The  result  of  this  criticism 
in  some  cases  may  be  that  the  entire  production  is  rejected,  even 
the  story  being  condemned  as  unsuitable  for  a  motion-picture  sub- 
ject, or  the  producer  may  be  required  to  reproduce  the  entire  drama 
or  certain  parts  of  it.  Perhaps  some  actor  is  judged  unsuited  to  his 
part  and  all  scenes  in  which  he  has  appeared  must  be  retaken 
with  another  actor  substituted. 

Padding.  \Mien  making  each  scene,  the  producer  had  before 
him  a  schedule  for  the  length  of  each  scene  in  the  drama  to  produce 
the  total  length  required.  In  the  review  and  criticism,  some  scenes 
may  be  cut  in  length  and  others  omitted  for  cause.  If  this  reduces 
the  total  length  of  action  scenes  below  the  required  amount,  scenes 
may  be  substituted  to  fill  out,  or  the  remaining  scenes  may  be  left 
a  little  longer  than  their  predetermined  or  required  lengths.  This  is 
"padding"  the  film.  As  an  example  of  what  might  be  done  at  the 
risk  of  spoiling  a  good  film  picture,  "A  ^Midnight  Cupid"  might  open 
with  the  village  cottage  scene  setting,  girl  despondent  talks  to  father, 
brings  paper  and  pen,  father  writes,  then  show  title  the  letter  which 
the  tramp  reads  in  Scene  1.  A  scene  of  the  tramp's  troubles  seeking 
food  and  expressing  hunger  may  be  inserted  between  Scenes  1  and  2. 


108 


42  THE  MOTION  PICTURE 

Between  Scenes  7  and  8,  scenes  showing  the  club  man  en  route 
to  the  country  may  be  inserted,  and  between  Scenes  25  and  26,  scenes 
of  all  the  characters  en  route  might  be  added.  Distinction  may  be 
drawn  between  a  scene  added  to  lengthen  the  film  and  a  scene  added 
for  the  purpose  of  strengthening  the  telling  of  the  story,  only  the 
former  being  "padding." 

Rewriting.  The  scenes  and  their  order  being  determined, 
the  producer  must  correct  the  synopsis  and  perhaps  other  parts  of 
the  scrip  to  fit  the  completed  drama  if  any  correction  is  necessary. 
Particularly  in  the  review  and  criticism  is  the  matter  of  titles  dis- 
cussed, and  titles  in  correct  and  final  form  are  determined.  In  the 
corrected  synopsis,  the  length  of  each  scene  and  of  each  title  is  noted. 

Titles.  The  titles  are  made  by  the  producer  or  under  his  direc- 
tion and  are  given  to  the  photographer  to  be  done  into  film.  The 
title  is  painted,  printed,  written,  typewritten,  or  drawn,  or  made 
of  movable  letters  arranged  upon  a  support  and  removed  after 
photographing  to  be  rearranged  for  other  titles.  The  size  may  be 
anything  desired.  The  length  of  film  for  a  title  should  be  proportioned 
to  the  number  of  words  in  the  title,  being  thus  proportioned  to  the 
length  of  time  which  the  spectator  requires  to  read  it.  Two  feet  is 
enough  for  a  single  word,  and  a  foot  per  word  may  be  taken  as  a  rule 
for  titles  longer  than  half  a  dozen  words. 

A  sign  writer  who  personally  prefers  a  full  arm  movement 
would  paint  the  titles  on  a  sheet  probably  4^  by  6  feet.  A  sign  writer 
who  prefers  to  use  a  small  brush  and  a  WTist  movement  would  work 
on  cards  probably  18  inches  by  24  inches.  In  either  case,  black  paint 
on  a  white  background  may  be  produced  as  such  in  the  finished  film 
picture,  or  it  may  be  reversed  by  the  photographer. 

A  very  satisfactory  title  is  produced  by  setting  up  the  words 
with  printer's  type  and  printing  the  title  upon  a  printing  press.  In 
such  a  case,  in  order  that  a  sharp  photograph  may  be  made,  the  original 
should  be  at  least  as  large  as  6  inches  by  8  inches. 

\Miere  movable  letters  are  used  for  titles,  it  is  necessary  only 
for  the  producer  to  give  to  the  photographer  a  written  title,  or  a 
sketch  of  the  word  arrangement  desired.  For  titles  in  the  nature 
of  messages,  letters,  telegrams,  etc.,  the  messages  may  be  printed 
with  printer's  script  type  and  handed  over  to  the  photographer. 
Such  a  title  probably  would  not  be  larger  than  3  inches  by  4  inches. 


110 


MOTOGRAPHY  43 

Written  messages  may  be  prepared  just  as  the  picture  screen 
is  to  show  them,  written  by  hand  with  black  ink  upon  white  paper. 
The  handwriting  of  the  message  should  be  consistent  with  the 
character  of  the  actor  writing  it,  and  should  show  creases  if  the 
message  has  been  folded  in  the  motion  scenes  of  the  play.  For  tele- 
grams, use  the  regulation  telegraph  blank.  Use  a  "send"  blank  for 
messages  to  be  sent  and  a  "received"  blank  for  messages  received. 
They  may  be  written  either  by  hand  or  typewriter. 

Borders  for  titles  or  trademarks  for  titles  may  be  incorporated 
into  the  titles  by  drawing  or  printing  the  title  upon  sheets  which 
have  been  printed  previously  with  the  border  or  trademark. 

A  "reversed  title"  is  a  name  given  to  titles  having  the  letters 
show  in  white  upon  a  dark  picture  screen.  This  effect  is  obtained 
directly  by  painting  with  wiiite  upon  a  black  background,  or  by 
arranging  movable  white  letters  upon  a  black  table,  but  it  may  be 
produced  from  black  letters  upon  a  white  ground  by  an  additional 
process  in  photographing.  It  is  not  suitable  of  course  for  messages. 
A  reversed  title  is  much  more  easily  read  and  is  much  more  accept- 
able to  the  audience  than  a  title  which  has  black  letters  upon  a  w'hite 
ground.    The  reversed  title  is  further  improved  by  tinting. 

Final  Criticism.  The  titles  being  completed,  and  added  or 
changed  scenes  having  been  reproduced,  the  proof  for  the  first 
criticism  has  each  scene  cut  to  its  prescribed  length  and  proofs  of 
the  titles  are  cut  to  their  prescribed  length  and  inserted  among 
the  motion  scenes  in  the  order  required  by  the  revised  synopsis. 
Thus,  there  is  produced  a  final  proof  picture  of  the  complete  film 
as  it  is  to  be  released  to  the  public.  The  final  proof  is  projected  before 
the  producer  and  critics  and  if  approved  it  is  turned  over  to  the 
photographer  as  "copy."  The  photographer  cuts  his  negative  into 
lengths,  both  motion  scenes  and  titles,  splicing  them  together  to 
reproduce  a  complete  continuous  negative  of  the  approved  "copy." 

Whether  the  film  be  drama,  comedy,  travel,  chase,  or  trick, 
the  procedure  of  motion-scene  production,  first  criticism,  rewriting 
scrip,  making  titles,  final  proof,  and  approval  of  copy  is  on  final 
criticism  in  substance  the  same. 

At  this  point,  the  film  picture  passes  out  of  the  hands  of  the 
producer  and  into  the  hands  of  the  salesman,  or  advertising  mana- 
ger of  the  producing  company. 


Ill 


44  THE  MOTION  PICTURE 

THE    SALESMAN 

The  salesman  of  the  film  manufacturing  company,  or  the  adver- 
tising manager,  as  his  title  usually  reads,  has  as  his  task  the  disposi- 
tion of  as  many  copies  of  the  finished  picture  (as  many  photographic 
prints  from  the  negative)  as  his  opportunity  and  ability  can  effect. 

Branches  of  the  Film  Industry.  The  customer  of  the  film  manu- 
facturer is  the  film  exchange  manager,  or  renter,  whose  customer 
in  turn  is  the  film  exhibitor.  The  film  industry  is  definitely  separated 
into  three  branches:  manufacturer,  renter,  and  exhibitor.  The  renter 
owns  the  picture  films.  He  buys  from  the  manufacturer  for  cash 
and  rents  the  films  to  the  owners  of  picture  theaters  for  exhibition. 
The  exliibitor  owns  no  films,  merely  renting  them  for  a  day  or  a 
week  from  the  renter;  the  manufacturer  owns  no  positive  picture 
films,  merely  printing  from  his  film  negatives  as  many  copies  of 
each  picture  as  can  be  disposed  of  immediately  to  his  customers, 
the  film  renters. 

Selling  Methods.  General  publicity  is  obtained  among  the 
renters  and  exhibitors  by  advertising  in  the  motion-picture  magazines. 
In  the  magazine  advertisements,  the  general  excellence  of  the  mg-nu- 
facturer's  film  pictures  is  told,  and  the  current  film  pictures  just 
produced  or  about  to  be  produced  are  announced  by  title  with  a  few 
descriptive  words  and  illustrations.  , 

Lectures.  The  magazine  advertising  is  supplemented  by  lec- 
tures or  short  stories  of  the  film  pictures.  The  lectures  derive  their 
name  from  the  original  purpose,  which  was  to  provide  a  talk  to 
accompany  the  picture,  explaining  the  story  of  the  picture  as  the 
action  progressed  on  the  screen.  While  the  original  purpose  of  lec- 
tures is  almost  extinct,  their  advertising  value  remains  and  they 
are  used  by  manufacturers  in  large  quantities.  Each  film  picture 
has  its  lecture  and  these  are  printed  either  separately,  or  in  a  little 
pamphlet  covering  the  manufacturer's  output  of  film  pictures  for 
the  week  or  for  two  weeks. 

The  lectures  are  written  by  the  salesman  or  his  assistants,  using 
the  corrected  synopsis  or  scrip  of  the  story  as  a  guide  and  keeping 
in  mind  at  all  times  the  film  as  actually  produced.  At  least  the 
motion  scenes  of  the  picture  should  be  produced  and  reviewed  by 
the  critics  before  the  film  is  advertised  for  release  and  before  the 


112 


MOTOGRAPHY  45 

lecture  is  written.  The  writer  of  the  lecture,  having  sat  at  the  pro- 
jection of  the  proofs  for  the  preUminary  review,  will  be  further  guided 
in  writing  the  lecture  by  his  recollection  of  the  strongest  scenes  of 
the  production.  The  lecture  is  illustrated  by  views  of  the  film  taken 
from  the  scenes  either  by  clipping  a  small  image  from  a  copy  of  the 
proof  film  or  by  photographing  the  scene  with  a  hand  camera  upon 
a  larger  scale  while  the  picture  is  being  produced.  In  either  case, 
the  engraver  is  able  to  produce  printing  blocks  of  the  desired  size 
for  the  lecture. 

Lectures  are  mailed  in  advance  of  the  release  date  of  the  film. 
They  are  sent  to  the  magazine  publishers  that  they  may  be  printed 
in  the  magazines  either  in  full  or  in  part,  for  additional  advertising 
value  to  the  manufacturer.  They  are  sent  to  the  film  exchanges 
that  the  renters  may  know  what  pictures  are  promised  for  the  ad- 
vance dates.  They  are  sent  to  the  exhibitors  that  the  exhibitors 
may  be  impressed  by  the  lecture  that  the  film  is  especially  suited  to 
their  particular  audiences  and  that  the  exhibitors  may  ask  the  renters 
for  the  picture  and  the  renter  thus  be  obliged  to  buy  the  film  from 
the   manufacturer. 

Release  Dates.  The  routine  of  manufacturing  and  selling  motion- 
picture  films  can  be  compared  very  closely  with  the  routine  of  print- 
ing and  selling  a  newspaper  or  magazine. 

The  amusement  business  is  established  upon  a  weekly  basis. 
In  theatrical  circles,  a  year  is  spoken  of  as  fifty-two  weeks,  and  a 
day  one-seventh  of  a  week.  The  big  theaters  change  their  bills  at 
the  end  of  the  week,  and  the  vaudeville  programs  are  changed  weekly 
Similarly,  in  the  motion-picture  theater,  the  program  is  made  upon 
a  weekly  basis,  the  film  renter  makes  his  schedules  upon  a  weekly 
basis,  and  it  best  suits  his  convenience  to  receive  his  films  from  the 
manufacturers  upon  a  weekly  schedule.  As  the  business  man  gets 
his  newspaper  every  morning,  so  the  prominent  "daily  change" 
motion-picture  theater  gets  its  new  film  every  morning  from  the 
renter,  who,  in  turn,  gets  films  every  morning  from  the  various  manu- 
facturers. Orders  are  placed  by  the  renter  on  a  basis  of  weekly 
deliveries,  that  his  schedule  may  run  smoothly.  Monday  morning 
brings  a  reel  from  manufacture^  A,  Tuesday  a  reel  from  B,  Wednes- 
day a  reel  from  C,  Thursday  another  reel  from  A,  Friday  another 
reel  from  B,  and  Saturday  a  reel  each  from  D  and  E.    These  de- 


ns 


46  THE  MOTION  PICTURE 

liveries  are  repeated  weekly,  giving  a  constant  schedule  of  seven 
reels  per  week,  combining  the  product  of  several  manufacturers. 

In  view  of  the  deliveries  required  by  his  customer,  the  renter, 
the  manufacturer  is  obliged  to  issue  his  pictures  as  regularly  and 
as  punctually  as  a  publisher  issues  his  magazine  to  the  newsdealer. 
Each  film  manufacturer,  therefore,  establishes  one  or  more  release 
davs  for  each  week,  according  to  the  number  of  reels  of  film  which 
he  will  manufacture  per  week,  and  advertises  that  a  full  reel  of  film 
will  be  sold  or  "released"  upon  each  of  his  release  days. 

Advance  Shipments.  It  has  been  found  convenient  to  release 
a  picture  in  all  parts  of  the  United  States  upon  its  release  date,  and 
this  is  accomplished  by  advance  shipments  to  discount  the  time  in 
transit,  and  by  shipments  further  advanced  to  discount  the  likely 
delays  in  transit.  A  New  York  manufacturer  will  ship  his  pictures 
to  San  Francisco  customers  seven  days  in  advance  of  his  release 
date;  to  Denver  or  New  Orleans  customers  five  days  in  advance  of  his 
release  date;  to  his  Chicago  and  St.  Louis  customers  three  days  in  ad- 
vance; to  Philadelphia  and  Boston  customers  two  days  in  advance;  and 
will  deliver  by  messenger  to  New  York  customers  on  the  evening 
before  the  date  of  release.  In  the  case  of  the  distant  shipments,  the 
films  should  arrive  two  or  three  days  ahead  of  the  release  date,  but 
the  renter  is  honor  bound  to  issue  them  to  the  exhibitor  only  on  and 
after  the  release  date.  In  case  it  comes  to  the  attention  of  any 
manufacturer  that  any  renter  is  violating  the  release  date,  the 
advance  shipment  for  discounting  delays  in  transit  will  be  with- 
held. 

Factory  Schedule.  A  safe  schedule  for  insuring  the  release  of 
the  picture  film  to  the  renter  promptly  upon  the  release  date  carries 
the  beginning  of  the  work  of  making  the  film  back  to  a  date  many 
weeks  before  release.  A  picture  to.be  released  on  May  6,  if  manu- 
factured in  New  York,  must  be  shipped  to  the  San  Francisco  and 
Los  Angeles  customers  a  week  in  advance,  on  April  29.  The  photog- 
rapher must  have  time  in  advance  of  this  to  enable  him  to  print  the 
pictures  from  the  negative,  so  the  approved  "copy"  of  the  film  must 
be  delivered  to  the  photographer  on  April  22,  two  weeks  in  advance 
of  release  date,  that  he  may  fit  his  negative  to  the  "copy"  and  begin 
printing  in  time  for  the  west  coast  shipment.  Inasmuch  as  the  final 
criticism  may  require  changes  before  the  "copy"  is  approved,  the 


114 


MOTOGRAPHY  47 

projection  of  the  picture  for  final  criticism  is  set  for  April  15,  three 
weeks  in  advance  of  release  date.  Between  projection  of  the  motion 
scenes  for  preliminary  criticism  and  projection  for  final  criticism, 
one  week  is  not  sufficient  for  remaking  condemned  scenes,  produc- 
ing padding  scenes,  rewriting  the  scrip  and  maldng  the  titles.  Par- 
ticularly in  view  of  the  possibility  that  the  entire  picture  may  be 
rejected,  an  interval  of  three  weeks  is  none  too  short  between  pre- 
liminary review  and  final  review  in  the  ordinary  progress  of  the 
factory.  The  date  for  preliminary  criticism  is  set  for  six  weeks  in 
advance  of  release,  or  March  25  for  preliminary  criticism  for  the 
May  6  release.  For  ordinary  productions,  give  the  producer  a 
latitude  of  two  weeks  for  his  motion  scenes,  and  two  weeks  preced- 
ing for  preparation  of  his  scenery  and  properties,  taking  the  delivery 
of  the  scrip  to  the  producer  back  to  ten  weeks  in  advance  of  release 
date,  or  February  25,  for  the  release  of  May  6.  Still  back  of  this 
date  is  the  writing,  criticism,  and  acceptance  of  the  original  scrip. 
Some  pictures,  particularly  trick  pictures,  may  recjuire  many  weeks 
for  the  production  of  the  motion  scenes. 

In  contrast  with  this  is  the  story  told  of  an  eastern  factory, 
that  an  actor  in  the  noon  hour  suggested  to  the  producer  a  thought 
for  a  comedy,  that  the  producer  dropped  the  work  in  hand  and  had 
the  first  scene  of  the  new  comedy  on  at  two  o'clock  the  same  after- 
noon, and  scenes  were  completed  for  a  fidl  comedy  reel  the  follow- 
ing day.  In  contrast  also  is  the  method  of  a  producer  who  habitually 
worked  without  scrip  or  scenario,  producing  only  his  own  creations, 
direct  from  brain  to  film. 

Sales  Contracts.  The  usual  order  accepted  by  the  manufac- 
turer from  the  renter  is  an  order  for  a  predetermined  number  of 
reels  per  week — usually  one  copy  of  each  picture  produced  by  the 
factory.  Such  an  order  gives  the  manufacturer  advance  knowl- 
edge of  the  quantity  of  his  output  and  it  is  by  such  orders  only  that 
a  manufacturer  is  enabled  to  work  upon  so  close  a  schedule  as  the 
one  cited — giving  but  two  weeks  between  the  final  approval  of  the 
"copy"  of  the  picture  to  the  release  date.  If  it  becomes  necessary 
for  the  salesman  to  exhibit  an  advance  copy  of  the  finished  picture 
as  a  means  for  getting  orders  for  the  films,  several  additional  weeks 
must  be  inserted  in  the  schedule  between  the  final  approval  of  the 
"copy"  and  the  date  of  the  release  of  the  film. 


115 


48  THE  MOTION  PICTURE 

Title  Posters.  To  advertise  his  program  to  the  passers-by, 
the  theater  manager— or  "exhibitor,"  as  he  is  known  in  the  trade 
— displays  the  titles  of  his  pictures  in  front  of  his  entrance.  The 
salesman  for  the  film  manufacturer  provides  for  attractive  posters 
for  the  films  released,  either  by  furnishing  them  to  the  exhibitor 
directly  through  the  film  exchange  to  whom  the  salesman  sells  the 
film,  or  by  providing  necessary  information  to  title  poster  com- 
panies to  enable  them  to  offer  attractive  title  posters  to  the  exliibitor. 

REPRODUCTION 
THE  PHOTOQRAPHER 

If  the  factory  is  to  be  considered  as  distinct  from  the  studio, 
and  from  the  o^ce,  then  the  office  is  the  department  of  the  sales- 
man, the  studio  is  the  department  of  the  producer,  and  the  factory 
is  the  department  of  the  photographer.  "Factory  superintendent" 
perhaps  would  be  a  suitable  title  for  this  photographer,  for  he  does 
but  little  of  the  photographic  work  with  his  own  hands.  The  di- 
visions of  his  factory  taken  in  the  order  in  which  they  become  useful 
in  the  making  of  a  picture  film,  are  as  follows : 

Divisions  of  the  Photographic  Factory.  The  raw  sensitive  film 
is  purchased  cut  to  size  and  packed  in  tin  cans.  A  fireproof  iron 
safe  or  a  fireproof  vault  for  film  storage  holds  the  film  until  needed. 
From  the  vault,  it  is  taken  to  the  perforating  room,  where  holes  are 
punched  in  the  edges  Thence  the  negative  film-  goes  to  the  camera 
man,  who  is  the  photographer's  employe  working  under  orders  of 
the  producer.  From  the  camera  man  the  exposed  film  goes  to  the 
developing  room,  where  it  is  developed  into  a  negative.  Then  titles 
are  made.  Scenes  and  titles  being  finally  approved  and  spliced 
up  according  to  "copy,"  the  film  negative  goes  to  the  printing  room 
and  supplies  of  positive  film  also  go  from  the  perforating  room  to 
the  printing  room,  where  the  positive  film  is  printed  from  the  negative. 
The  negative,  after  all  prints  are  made,  goes  to  the  film  storage 
room  permanently.  The  printed  positive  film  goes  from  the  print- 
ing room  to  the  developing  room  which  developed  the  negative, 
then  to  the  washing  room,  then  to  the  drying  room,  and  when  dry 
to  the  inspection  and  splicing  room  and  again  to  the  fireproof  storage 
vault  until  the  day  for  packing  and  shipment.    In  brief,  the  divisions 


116 


MOTOGRAPHY  49 

of  the  photographer's  factory  are  film  storage,  perforating,  camera, 
developing,  title  making,  printing,  washing,  drying,  inspecting,  and 
shipping.      The  strip  film  is  bought  ready  for  perforating. 

The  total  task  of  the  photographer — or  "factory  superintend- 
ent" or  whatsoever  title  he  may  bear  in  various  film  manufacturing 
plants — is  to  produce  a  creditable  photographic  film  picture  when 
the  producer  has  enacted  the  scenes  and  has  written  the  titles.  This 
task  requires  the  photographer  to  have  his  assistant,  the  camera 
man,  present  when  the  producer,  enacts  a  scene,  and  leaves  the 
responsibility  upon  the  photographer — through  his  assistant,  the 
camera  man — for  the  proper  photographic  record  of  the  scene 
upon  the  negative  film  of  the  camera.  The  division  of  responsibility 
at  tliis  point  is  logical.  If  a  negative  is  lost  because  the  camera  man 
used  the  wrong  stop  in  the  lens,  the  failure  is  photographic  in  nature, 
and  the  photographer  is  to  blame  because  of  the  incompetency  of 
his  assistant.  From  this  point  to  the  delivery  of  the  film  for  shipment, 
the  processes  are  wholly  photographic.  The  photographer  assigns 
his  camera  men  to  the  producer  as  demanded,  providing  them  with 
negative  film,  and  delivers  proof  prints  to  the  producer  for  criticism. 
From  approved  proofs  and  picture  "copy,"  the  photographer  prints 
finished  film  pictures  as  requested,  and  delivers  them  by  shipping 
them  under  the  salesman's  orders. 

Raw  Film.  Compositio7i.  The  sensitive  film  before  use  in  the 
camera  consists  of  a  long  narrow  strip  of  celluloid  coated  with  a 
gelatine  photographic  emulsion.  Its  manufacture  is  distinctly  in 
two  parts,  the  making  of  the  celluloid  strip  and  the  making  of  the 
sensitive  emulsion  and  coating  the  celluloid  strip  with  the  emulsion. 
Neither  the  making  of  the  celluloid  nor  the  coating  should  be  at- 
tempted except  by  skilled  workmen  in  a  thoroughly  equipped  factory. 

Manufacture.  Celluloid  is  made  from  pyroxylin  and  camphor, 
the  pyroxyUn  or  guncotton  being  made  from  raw  cotton  by  treat- 
ing it  with  nitric  and  sulphuric  acids.  Sulphuric  and  nitric  acids 
are  mixed  in  practically  equal  quantities,  the  raw  cotton  is  dipped 
until  saturated  but  not  allowed  to  dissolve,  then  is  thoroughly  washed 
and  dried.  By  this  process  the  cotton  has  been  transformed  into 
guncotton,  an  article  very  explosive'  in  nature,  but  not  different  in 
appearance  from  the  original  raw  cotton.  The  camphor  is  dis- 
solved in  alcohol,  making  a  saturated  solution. 


117 


50 


THE  MOTION  PICTURE 


A  layer  of  drj'  pyroxylin  is  placed  in  a  tank  and  about  one- 
half  the  quantity  of  camphor  solution  is  sprinkled  over  it,  then 
pjToxylin,  then  camphor,  and  so  on.  The  pyroxylin  dissolves  in 
the  camphor  solution  and  celluloid  is  formed  in  lumps  which  sink 
to  the  bottom  of  the  tank.  The  lumps  of  celluloid  are  worked  be- 
tween rollers,  cold  and  hot,  and  pressed  in  hydraulic  presses  and 
dried. 

The  celluloid  stock  is  worked  into  thin  strips  for  motion-pic- 
ture work,  the  strips  being  1/200  of  an  inch  in  thickness.  The  width 
and  length  may  be  anything  desired,  say  22  inches  wide  by  200  feet 
long. 

Coating.  The  emulsion  for  coating  the  film  is  of  two  kinds, 
slow  for  prints  and  fast  for  negatives,  a  bromide  emulsion  for  the 
slow  and  a  nitrate  emulsion  for  the  fast.  The  emulsion,  made  as 
for  photographic  dry  plates  or  hand-camera  films,  is  placed  in  a 
coating  macliine  having  an  emulsion  hopper  and  a  sUt  to  feed  the 
emulsion  upon  the  celluloid.  The  22-mch  strip  of  celluloid  is  passed 
at  a  uniform  speed  through  the  machine  and  under  the  emulsion 
slit,  receiving  a  uniform  coating  as  the  emulsion  flows  out  upon  it. 
The  wide  strip  of  film  is  dried  and  taken  through  a  cutting  machine 
which  splits  it  into  strips  If  inches  wide  and  200  feet  long.  The 
narrow  strips  are  rolled  up  and  packed  in  round  flat  tin  cans,  sealed 
vvith  adhesive  tape,  one  strip,  or  200  feet  of  film,  in  each  can.  It  is 
now  ready  for  delivery  to  the  motion-picture  manufacturer 

N cM-hiflcnnmahle.  The  celluloid  base  of  the  motion-picture 
film  is  highly  inflammable,  although  not  explosive  in  that  it  will  not 
take  fire  unless  a  flame  is  applied  to  it  or  it  is  heated  to  a  very  high 
temperature  to  start  combustion.  The  heat  of  the  projecting  arc 
concentrated  upon  the  film  in  the  film  window  of  the  projecting  ma- 
chine is  sufficient  to  ignite  it.    ^^^len  ignited,  it  bums  rapidly 

Many  experiments  have  been  made  either  to  discover  a  sub- 
stitute for  the  inflammable  celluloid  for  use  in  motion-picture  work, 
or  to  discover  some  modification  of  the  process  ii  making  celluloid 
which  would  render  it  less  combustible.  By  adding  amyl  silicate 
or  methyl  silicate  to  the  vat  in  which  the  pyroxylin  and  camphor 
are  combined,  a  sufficient  quantity  of  silica  may  be  added  to  the 
celluloid  to  reduce  its  inflammability  so  that  it  will  burn  very  slowly, 
if  at  all.     The  addition  of  calcium  chloride  to  the  celluloid  com- 


118 


MOTOGRAPHY 


51 


pound  also  produces  a  similar  result.  The  finished  mass  of  new 
celluloid  while  still  soft  may  be  treated  with  stannous  chloride, 
rendering  it  less  easily  combustible. 

A  non-inflammable  product  made  by  combining  camphor 
with  an  acetate  cellulose  instead  of  with  a  nitrate  cellulose,  or  pyroxy- 
lin, has  been  used  widely  as  a  substitute  for  the  inflammable  celluloid 
strip  for  motion  films.  This  is  the  "N.  I."  commercial  film,  and 
gives  satisfactory  senice  for  a  short  life. 
Its  objectionable  point  is  that  with  age 
and  the  heat  of  the  projecting  arc  it 
shrinks  to  some  extent  and  becomes  some- 
what brittle. 

Storage  of  Film.  The  greatest  care 
must  be  taken  in  selecting  a  place  for  the 
storage  of  the  raw  film,  as  also  for  the 
storage  of  the  finished  pictures  before 
shipment,  and  for  the  storage  of  the  film 
negatives,  the  most  valuable  of  all,  par- 
ticularly during  the  period  between  pre- 
liminary approval  and  the  release  of  the 
picture.  The  storage  room  must  be  so 
situated  and  constructed  that  the  film  will 
be  kept  safe  from  flames  and  will  be  kept 
cool.  \Mien  warm,  celluloid  gives  off  ex- 
plosive gases  rapidly.  A  vent  pipe  for 
such  gases  may  be  formed  by  a  pipe  of 
small  size  leading  to  the  open  air  and 
guarded  with  steel  wool  or  gauze  to  pre- 
vent backfiring. 

Perforation  of  Film.  The  standard 
perforation  is  four  holes  per  picture,  or 
rather  four  pairs  of  holes  per  picture. 
Each  hole  is  approximately  j\  inch  by 
/^  inch,  spaced  along  the  edges  of  the 
strip  of  film  at  a  distance  of  -^  inch 
apart,  maldng  four  holes  on  each  edge  for  each  f-inch  motion- 
picture  image.  The  photographic  images  being  1  inch  wide,  and 
the  film  strip  If  inch,  the  pictures  being  also  in  the  middle  of  the 


Fig.  10. 


Specimen  of 
Positive  Film 


119 


52 


THE  MOTION  PICTURE 


strip,  there  remains  a  margin  of  ^\  inch  on  each  side  of  the  strip 
for  the  feed  holes.  The  perforations  are  placed  in  this  margin,  not 
centrally  in  the  margin,  but  against  the 
side  of  the  image  to  leave  as  wide  an  edge 
of  celluloid  outside  of  the  perforations  as 
possible  to  strengthen  them  against  break- 
ing out  to  the  edge.  In  the  illustration  of 
a  specimen  of  picture  film,  Figs.  10  and  11, 
the  perforations  seem  to  encroach  upon  the 
photographic  images.  Indeed,  in  the  pro- 
jected picture  upon  the  screen,  the  edges 
of  the  perforations  sometimes  are  seen  at 
the  side  of  the  picture  because  of  a  lack  of 
proper  centering  of  the  film  in  the  project- 
ing machine. 

Shape.  The  three  shapes  of  perfora- 
tion commonly  used  are  known  as  round, 
square,  and  barrel.  They  are  illustrated  in 
Fig.  12.  The  square  and  barrel  holes  seem 
to  give  longer  life  to  the  film  than  the  hole 
having  the  round  form.  The  shape  of 
the  tooth  in  the  projecting  machine  which 
enters  the  film  perforation  and  by  which 
the  film  is  pulled  through  the  projecting 
machine  should  determine  the  shape  of  the 
hole.  The  tooth  most  commonly  met  has 
a  flat  pulling  face,  and  this  pulls  best 
against  the  flat  surface  edge  of  the  hole 
offered  by  the  shape  of  the  square  or  barrel 
perforation. 

Spacing.  The  sprocket  method  of  feed- 
ing the  film  allows  some  latitude  in  dis- 
tance of  perforations,  and  thus  cares  for 
slight  inaccuracies  in  the  perforating  ma- 
chines, and  for  the  variation  due  to  shrink- 
Fig.  11.  Negative  Film.  Motion  age  of  the  film  with  age  or  with  its  treat- 
;^th'"bTuc^s}:i°f'any'wh.tment  in  the  processes  of  development  and 
drying  after  leaving  the  perforator.      The 


apron. 
color:j.) 


(Film    shows    reverse 


120 


MOTOGRAPHY  53 

spacing  in  the  perforating  machine  should  be  -^^  inch  per  hole,  and 
it  should  be  uniform.  Careful  experiment  has  shown  that  the  films 
whose  sprocket  holes  wear  best  are  those  whose  sprocket  holes  are 
most  uniformly  punched,  regardless  of  whether  they  have  main- 
tained their  original  distances  or  have  been  subjected  to  change  by 
development  processes  or  by  age.  If  the  holes  are  not  uniform, 
one  hole  edge  will  get  more  than  its  share  of  pull  from  the  sprocket 
teeth,  and  that  hole  will  break  out,  its  neighbors  then  getting  an 
excess  strain  and  breaking  in  turn  until  the  film  must  be  cut  and 
spliced.  The  splice  in  passing  through  the  film  gate  places  an  abnor- 
mal strain  upon  the  edges  of  the  perforations  in  advance  of  it  and 


Fig.  12.     Shapes  of  Film  Perforations 

which  have  to  pull  it  through  the  gate.  Thus  the  trouble  started  by 
uneven  punching  is  cumulative  and  shortens  the  fife  of  the  film. 

Perforating  Machines.  Self-feeding  or  automatic  punch  presses 
for  punching  small  blanks  out  of  sheet  metal  may  be  seen  in  large 
machine  shops.  When  provided  with  proper  punches  and  dies 
they  become  suitable  for  perforating  motion-picture  film.  When 
the  punches  are  of  the  reciprocating  type,  a  group  of  eight  punches 
work  vertically  above  a  plate  having  holes  to  receive  the  punches 
and  having  guides  for  the  unperforated  strip  of  film.  Associated 
with  the  punches  are  two  "pilots,"  tapered  fingers,  which  come 
down  with  the  punches  and  pass  into  the  last  holes  of  the  film  strip, 
that  the  distance  from  the  last  holes  to  the  new  holes  ubout  to  be 
punched  may  be  exact.  .\n  intermittent  feed  device,  similar  to  that 
of  the  camera  or  projecting  machine,  worlvs  into  the  holes  of  the 
perforated  end  of  the  film  and  pulls  it  forward  one  picture  length 
between  the  strokes  of  the  punch.  Punches  of  this  type  may  be 
operated  at  speeds  of  500  to  1,000  feet  of  film  per  hour.  Only  one 
strip  at  a  time  is  punched. 

In  the  case  of  rotary  punches,  two  drums  are  built,  one  of  which 


121 


54  THE  MOTION  PICTURE 

has  in  its  face  recesses  corresponding  to  the  holes  of  the  finished 
film  and  the  other  of  which  has  teeth  to  match  the  recesses  of  the 
first  drum.  The  teeth  are  of  such  length  that  they  reach  to  the 
edge  of  the  recesses  of  the  companion  drum  but  do  not  enter.  The 
drums  are  revolved  in  unison  and  the  film  strip  is  passed  between 
them.  Revolving  brushes  keep  the  punched-out  pieces  from  follow- 
ing around  the  drums  and  entering  again.  Rotary  punches  are  of 
high  capacity,  being  able  to  perforate  film  at  a  rate  of  5,000  feet  or 
more  per  hour.  They  are  more  likely  to  get  out  of  accurate  adjust- 
ment than  the  reciprocating  punch,  and  are  more  difficult  to  sharpen 
when  dulled  by  service. 

Perforating  Room.  The  perforating  room  is  a  darkroom, 
photographically  dark  while  the  perforating  machines  are  working 
the  film.  It  is  only  when  all  film  is  safely  shut  in  the  tin  cans  that 
the  white  light  may  be  turned  on  or  the  door  opened.  It  has  a  "light- 
trap"  entrance,  or  in  the  wall  is  built  a  turntable  with  four  wings, 
like  the  revolving  doors  of  a  store  or  office  building,  encased  light 
tight,  with  a  window  into  the  turntable  inside  the  darkroom  and 
another  outside.  By  this  turntable,  a  few  cans  of  punched  film  may 
be  passed  out  on  demand  without  waiting  for  the  punching  machines 
to  finish  their  strips  of  film  to  permit  the  door  to  be  opened. 

Camera  Man.  Only  a  photographer  who  has  demonstrated 
his  ability  to  make  good  negatives  with  the  fixed  camera  under 
varying  conditions  should  attempt  to  qualify  for  the  position  of 
camera  man  with  a  motion-picture  factory.  Upon  the  camera  man, 
as  representative  of  the  factory  photographer,  rests  the  responsi- 
bility for  getting  a  good  negative  of  the  scene  enacted  by  the  pro- 
ducer. A  photographer  who  can  make  a  good  fixed  camera  negative 
of  the  scene  setting  can  acquire  easily  the  necessary  skill  in  turning 
the  camera  crank  at  a  uniform  rate  of  speed,  and  then  is  fully  com- 
petent to  make  a  thousand  motion-picture  images  of  the  same  scene 
while  the  action  of  the  scene  is  taking  place. 

Camera.  The  professional  motion-picture  camera  should  have 
the  following  features:  A  well-halanced  intermittent  movemetU, 
turning  smoothly  and  uniformly  in  all  crank  positions;  an  adjustable 
shidtcr,  adjustable  to  give  a  variable  ratio  between  the  "open  time" 
and  "closed  time"  of  the  film  window  for  each  revolution  of  the 
shutter,  that  is,  for  each  picture  made  upon  the  film  strip;  two  or 


128 


MOTOGRAPHY  55 

more  lenses  fitting  into  the  same  mount  or  flange  ring,  the  lenses  being 
of  different  focal  length  for  changing  the  angle  of  the  view  or  the 
size  of  the  images  in  the  film  window  and  for  decreasing  or  increasing 
the  depth  of  the  field  for  action  in  the  scene;  focusing  mount  for  the 
lenses,  either  having  each  of  the  lenses  in  its  own  focusing  mount  or 
preferably  having  a  single  focusing  mount  into  which  any  one  of 
the  different  lenses  may  be  inserted;  a  sliding  lens  hoard,  equivalent 
to  the  rising  and  falling  front  of  the  fixed  camera;  detachable  light- 
tight  film  boxes,  equivalent  to  the  dark  slides  of  the  fixed  camera 
preferably  of  such  construction  that  the  film  boxes  may  be  inter- 
changed without  opening  the  mechanism  compartment  of  the  camera; 
a  trick  picture  crank;  a  reversing  crank  or  a  reversing  tripod  socket; 
a  detachable  main  crank  or  preferably  a,  folding  main  crank;  a  level; 
a  finder  for  panoraming;  a  finder  for  focusing  window,  for  focusing 
without  opening  the  camera;  an  indicator  showing  the  amount  of 
film  used  and  unused  at  any  instant;  a  speed  indicator  showing  at 
any  instant  the  speed  (in  pictures  per  second)  at  which  the  camera 
is  being  turned;  difilm  marker  which  may  be  operated  from  the  outside 
of  the  camera  to  mark  upon  the  film  an  indication  of  the  position 
of  the  film  window  upon  the  film;  a  stiff  tripod  with  panoram  head; 
a  carrying  case.  In  addition  to  providing  for  the  panoraming  move- 
ment or  horizontal  swinging  movement  of  the  camera  upon  the 
tripod,  the  tripod  head  sometimes  provides  for  a  rocking  movement 
of  the  camera  vertically. 

In  size,  motion-picture  cameras  vary  greatly,  even  when  built 
to  carry  the  standard  size  film,  If  inches  wide,  and  the  standard 
quantity  of  a  200-foot  reel.  The  comparative  size  of  camera  and 
man  is  seen  in  several  of  the  figures.  The  Urban  camera  is  about 
18  by  18  by  6  inches.  Others  have  been  made  showing  a  front 
6  by  10  and  a  depth  of  14  inches.  Some  cameras,  as  the  Urban, 
carry  the  film  boxes  inside  the  camera  case,  while  others  attach  the 
film  boxes  to  the  outside  of  the  case,  thus  making  the  size  of  the 
camera  case  alone  seem  deceptive  when  given  in  figures.  The  weight 
of  a  camera  will  vary  from  eight  to  twenty  pounds. 

Film  Movement.  Successful  cameras  have  been  built  by  con- 
structing a  light-tight  box  for  the  motion  head  of  a  projecting  machine. 
Such  an  arrangement  fills  all  requirements  although  it  may  make 
a  bulky  camera.    The  limitations  in  building  a  film  shift  for  a  camera 


123 


56  THE  MOTION  PICTURE 

are  less  rigid  than  those  placed  upon  the  projecting  machine,  because 
of  the  shorter  period  of  rest.  In  the  projecting  machine,  the  film 
must  be  at  rest  for  at  least  eighty  per  cent  of  the  time,  and  must 
be  shifted  in  the  remaining  twenty  per  cent  of  the  picture  interval. 
In  the  camera,  the  intermittent  mechanism  may  be  such  as  to  use 
forty  per  cent  of  the  picture  interval  in  movement  if  desired. 

The  margin  of  safety  for  a  good  picture  in  a  camera  is  of  greater 
importance  than  in  a  projecting  machine.  If  the  projecting  machine 
is  out  of  order,  it  is  known  immediately  by  the  result  upon  the  screen, 
and  the  machine  is  adjusted.  If  the  camera  is  in  any  way  out  of 
order,  it  is  known  only  when  the  films  are  developed  at  the  end  of 
the  day's  work,  with  the  result  that  the  day's  work  must  be  done 
over  by  the  producer. 

The  film  in  the  camera  must  be  motionless  during  the  interval 
of  exposure  to  the  lens.  The  claw  type  of  intermittent  movement 
seems  well  adapted  to  this  end,  since  the  claws  may  advance  into 
the  perforations,  seize  and  pull  down  the  film  and  retire  from  the 
perforations  entirely,  leaving  the  film  entirely  out  of  contact  with 
the  film  shifting  mechanism  and,  therefore,  to  the  greatest  degree 
unaffected  by  the  driving  devices  which,  were  there  any  actual  con- 
tact between  the  driving  devices  and  film,  might  cause  a  slight  move- 
ment. During  the  period  of  rest  of  the  film  the  claws  return  to  the 
position  from  which  they  advance  into  the  perforations  to  give  the  film 
its  next  step,  and  during  this  interval  the  exposure  of  the  film  to  the 
lens  is  made.  That  the  claw-shift  mechanism  subjects  the  film  to 
greater  wear  than  the  sprocket  movement  becomes  of  less  import- 
ance in  the  camera  than  in  the  projecting  machine,  since  the  film  is 
run  through  the  camera  but  once. 

In  addition  to  the  Edison  camera,  using  the  sprocket  with 
perforated  film  strip,  and  the  Urban,  Gaumont,  and  many  others 
using  the  claw  movement  with  perforated  film  strip,  all  of  which 
use  intermittent  movement  of  the  film,  there  are  two  other  classes 
of  cameras — those  which  do  not  use  the  intermittent  film  movement 
and  those  which  do  not  use  the  perforated  film.  The  object  in  the 
use  of  cameras  avoiding  the  perforated  film  and  the  intermittent 
movement  usually  is  found  in  an  intent  to  avoid  patents  bearing 
upon  those  features.  The  Bianchi  camera,  used  by  Columbia 
licensees,  makes  pictures  upon  a  continuously  moving  film.     The 


124 


I 


MOTOGRAPHY  57 

Hamacek  camera  uses  an  unperforated  film,  the  film  being  perforated 
after  development  of  the  negative. 

Loading  Film  Holders.  Each  film  holder  consists  of  a  black 
box  of  thin  wood  with  door  and  spindle.  One  side  of  the  box  opens 
as  a  door,  either  hinged  or  entirely  removable.  The  spindle  or  hub 
passes  through  both  sides  of  the  box,  back  and  door,  turning  in 
journal  boxes  carried  by  the  back  and  the  door,  and  usually  being 
removable  from  the  box  merely  by  hfting  out  when  the  door  is  open. 
The  hub  has  a  clip  or  slot  for  attaching  the  end  of  the  film,  so  that 
the  film  may  be  wound  upon  the  hub  when  the  hub  is  turned.  Upon 
the  end  of  the  hub — usually  upon  that  end  which  projects  through 
the  back  of  the  film  holder,  but  in  the  case  of  the  removable  hub 
the  two  ends  should  be  alike — is  a  key  way  whereby  the  film  move- 
ment of  the  camera  may  engage  the  hub  and  turn  it  to  wind  up  the 
film.  The  key  is  a  slot  or  a  pair  of  holes  for  pins,  and  in  the  camera 
at  the  position  for  the  take-up  film  holder  is  a  key  corresponding  to 
the  key  way. 

The  negative  film  will  be  supplied  from  the  factory  storage 
vault  in  rolls  of  200  feet,  perforated,  rolled  with  an  open  center 
a  Httle  larger  than  the  hub  of  the  film  box  of  the  camera,  and  packed 
in  a  round,  flat  tin  can  sealed  with  adhesive  tape.  In  loading  an 
empty  film  holder,  it  is  necessary  only  to  open  the  door  of  the  holder, 
open  the  tin  box  (in  the  darkroom),  drop  the  roll  of  film  over  the 
spindle,  pass  the  end  of  the  film  through  the  slot  of  the  holder,  and 
close  the  holder. 

In  reloading  a  film  holder  containing  exposed  film,  the  proc- 
esses are  different,  depending  upon  whether  the  holder  has  a  remov- 
able spindle  or  hub,  and  whether  an  extra  hub  is  at  hand  for  reloading 
the  removable  hub  type  of  box.  \Mien  the  removable  hub  type  of 
film  holder  is  used,  the  factory  should  provide  an  extra  hub  with  each 
roll  of  negative  film,  packing  it  in  the  tin  box  in  the  hollow  center 
of  the  film  roll.  To  reload,  the  camera  man  opens  (in  the  darkroom) 
both  tin  film  box  and  camera  film  holder,  removes  the  new  film 
from  the  box,  lifts  the  exposed  film  from  the  camera  film  box  to  the 
tin  box  without  renioving  the  hub,  upon  which  the  film  is  wound 
tightly,  and  seals  the  tin  box  with  the  adhesive  tape.  He  then  fits 
the  new  hub  to  the  film  holder,  drops  the  new  roll  of  film  over  it, 
threads  the  end  of  the  film  through  the  slot,  and  closes  the  fihn  holder. 


125 


58  THE  MOTION  PICTURE 

In  reloading  the  film  holder  in  which  the  hub  is  not  removable, 
the  camera  man  must  have  a  film  winder,  winding  the  film  out  of 
the  holder,  then  changing  the  new  roll  of  film  from  the  tin  box  to 
the  film  holder,  and  then  the  exposed  film  from  the  winder  to  the 
tin  box. 

Exposed  and  Unexposed  Films.  Safeguards  are  necessary  to 
avoid  the  accidental  exposure  of  the  same  film  twice  in  the  camera, 
either  from  the  mistake  of  putting  an  exposed  film  holder  back  in 
the  camera  or  from  the  mistake  of  reloading  an  exposed  film  from 
its  tin  box  back  into  the  film  holder  and  thence  to  the  camera.  In 
short,  there  should  be  some  signal  to  indicate  that  the  roll  of  film 
has  been  exposed,  similar  to  the  turning  of  the  dark  slide  of  a  plate- 
holder. 

The  outside  end  of  an  unexposed  roll  should  have  its  corners 
clipped  to  faciUtate  threading  through  the  camera  when  loading. 
The  inner  end  should  be  left  square.  A  roll  with  the  outer  end 
square,  therefore,  is  an  exposed  roll. 

WThen  the  film  holder  is  loaded,  the  leading  end  of  the  film  is 
threaded  through  the  slot  of  the  holder,  and  projects  to  be  pulled 
out  and  threaded  up  in  the  camera.  When  the  roll  is  exposed,  it  is 
wound  up  completely  into  the  take-up  holder,  so  that  the  end  of  the 
film  does  not  extend  from  the  exposed  holder. 

In  a  camera  having  holders  with  removable  spindles  or  hubs, 
the  exposed  roll  of  film  will  have  a  hub  in  its  center  upon  which  the 
film  is  tightly  wound.  The  unexposed  film  will  have  the  hub  in  the 
tin  box,  perhaps,  but  the  film  will  not  be  tight  upon  it. 

In  a  camera  without  removable  spindles,  a  roll  of  film  which 
has  been  removed  by  the  camera  man  in  reloading,  probably  will 
have  a  different  size  of  center  hole  from  the  roll  received  from  the 
factory  film  storage  room. 

Tin  boxes  containing  unexposed  negative  film  in  the  factory 
storage  room  should  be  wrapped  in  paper  and  the  wrapper  pasted 
shut  so  that  the  paper  must  be  torn  to  get  it  off.  WTien  reloading 
film  holders,  the  camera  man  does  not  wrap  the  tin  cans  of  exposed 
film,  hence  the  only  fresh  film  the  camera  man  has  is  the  film  in 
the  wrapped  boxes  and  in  the  film  holders  with  the  leading  end  stick- 
ing out. 

In  addition  to  all  other  precautions,  the  exposed  film  should  be 


126 


MOTOGRAPHY  59 

sent  in  to  the  factory  as  soon  as  exposed,  but  even  then  the  factory 
may  send  back  an  exposed  roll  to  the  camera  man,  and  danger  sig- 
nals should  be  watched  for. 

For  studio  work  and  field  work  close  to  the  factory,  film  holders 
may  be  loaded  in  the  factory  darkroom.  \Miere  the  camera  man 
is  in  a  distant  city  or  still  worse  in  the  country,  it  may  be  necessary 
to  transfer  film  from  tin  cans  to  camera  film  holders  when  no  dark- 
room is  available.  A  bedroom  closet  will  serve  if  an  assistant  out- 
side will  hang  clothing  or  bed  clothing  over  the  cracks  of  the  door 
until  the  camera  man  inside  can  see  no  hght,  KneeUng  on  the  floor 
at  the  bedside  with  the  hands  (and  films  and  boxes)  under  the  covers, 
either  at  night  or  with  shades  drawn  and  a  bed  cover  hung  over  the 
window,  the  camera  man  may  work  by  touch.  Have  an  empty 
tin  can  and  as  a  first  operation  transfer  the  film  to  the  can  and  as  a 
second  operation  transfer  the  film  from  a  new  can  to  the  film  holder. 
In  the  field,  if  the  emergency  arise,  take  off  the  coat  and  shove  the 
arms  through  the  sleeves  the  wrong  way,  changing  the  film  inside 
the  coat.  An  assistant  supplies  the  film  and  boxes  to  the  hands  in- 
side the  coat,  and  muffles  it  further  by  any  available  clothing.  Get 
in  the  deepest  shadow  available.  For  all  these  emergency  methods 
it  may  be  borne  in  mind  that  the  roll  of  film  is  largely  self-protecting. 
On  the  sides  of  the  roll,  the  Hght  must  penetrate  3/16  inch  before 
reaching  the  latent  images,  the  inner  layers  are  hght-struck  by  the 
acts  of  loading  the  camera  and  they  serve  to  protect  the  following 
layers,  while  on  the  outer  layers  there  may  be  left  several  layers  of 
unused  film  for  protection  if  the  emergency  reloading  is  known  in 
advance. 

Loading  the  Camera.  The  loading  of  the  camera  is  an  opera- 
tion designed  for  daylight  work.  It  is  no  more  difficult  than  thread- 
ing a  film  through  a  projecting  machine.  The  full  take-up  film  holder 
is  removed.  The  empty  film  holder  is  taken  from  the  feed  position 
and  fastened  securely  in  the  take-up  position,  the  hub  being  connected 
with  the  mechanism  of  the  camera,  and  the  handle  given  a  few  turns 
to  ascertain  that  the  hub  is  turning  properly  to  take  up  the  exposed 
film.  A  loaded  filmholder  then  is  placed  in  the  feed  position  and 
the  end  of  the  film  pulled  out  to  reach  the  feed  mechanism.  A 
brush  should  be  attached  to  the  inside  of  the  camera  door  by  a  spring 
clip,  and  the  inside  of  the  camera,  particularly  the  film  window, 


127 


60 


THE  MOTION  PICTURE 


should  be  brushed  carefully  to  remove  minute  particles  of  celluloid 
or  other  dust  particles  left  by  the  previous  roll  of  film  in  passing 
through  the  machine.  The  new  film  then  is  passed  through  the 
upper  steady  feed,  through  the  intermittent  feed,  and  through  the 
lower  steady  feed,  to  the  take-up  film  holder,  passed  through  the 
slot  of  the  holder  and  attached  to  the  take-up  hub.  The  take-up 
holder  is  closed,  and  the  handle  is  given  a  turn  to  make  sure  that  the 
film  is  feeding  properly  and  that  the  take-up  holder  is  working  prop- 
erly. The  camera  ease  then  is  closed 
and  the  handle  is  turned  once  or 
twice  as  required  to  wind  past  the 
film  window  that  length  of  film  be- 
tween the  feed  film  box  and  the  film 
window  which  has  been  light-struck 
by  exposure  during  the  loading  of 
the  camera. 

In  Fig.  13  is  shown  the  Urban 
camera,  with  panoraming  and  ele- 
vating or  rocking  tripod  head.  The 
door  at  the  left  on  the  side  gives 
access  to  the  film  holders  and  feeds 
for  reloading  the  camera;  the  re- 
movable panel  in  front  gives  access 
to  the  intermittent  mechanism.  Fig. 
14  shows  the  Gaumont  camera,  open. 
In  this  camera  the  upper  and  lower 
constant  feeds  are  taken  from  the 
same  sprocket,  the  intermittent  feed 
mechanism  being  enclosed  in  a 
dust-proof  box  at  the  front  of  the 
camera.  The  feed  and  take-up  reels  are  external  to  the  camera  body 
and  have  a  very  large  capacity,  500  feet. 

Camera  Man's  Duties.  Taking  the  Picture.  To  set  up  his 
camera  when  instructed  by  the  producer,  to  include  the  scene  pointed 
out  by  the  producer,  to  begin  turning  and  to  stop  turning  when  told 
by  the  producer,  to  keep  his  camera  in  adjustment,  to  keep  an  ample 
supply  of  film  fotr  the  producer's  requirements,  and  to  turn  over  to 
the  factory  a  correctly  exposed  roll  of  film  having  upon  it  a  record 


128 


Fig.  13.     Urban  Camera 


MOTOGRAPHY 


61 


of  the  producer's  scene  from  the  word  ''start"  to  the  word  "stop." 
Turning  Crank.  At  the  top  of  the  illustration  of  the  Urban 
camera  is  a  round  window  in  which  a  finger  moves  over  a  scale 
marked  10-12-14-16.  When  the  handle  is  turned,  this  hand  in- 
dicates the  number  of  pictures  per  second  which  are  being  taken. 
The  usual  speed  is  fourteen  pictures  per  second.  Turning  the  crank 
at  a  uniform  speed  of  fourteen  pictures  per  second,  without  varia- 
tion in  the  speed  and  without  shaking  the  camera  upon  its  tripod, 


Fig.  14.    Gaumont  Camera 

can  be  done  only  after  much  practice.  Variations  are  liable  to  occur 
in  every  turn,  the  inexperienced  camera  man  turning  faster  as  the 
handle  comes  down  and  not  so  fast  as  it  is  passing  backward  at  its 
lowest  position.  They  are  liable  to  occur  also  by  steady  increase  or 
decrease  of  speed,  starting  a  scene  at  fourteen  and  finishing  it  at 
the  rate  of  ten  or  eighteen  pictures  per  second.  When  the  actors 
are  playing  their  parts  in  the  scene,  the  producer  is  prompting  them 
and   the  action   becomes  interesting  or  exciting,   the  new  camera 


129 


62  THE  MOTION  PICTURE 

man  is  liable  to  become  interested  or  excited  also  and  either  turn  the 
crank  so  fast  that  his  negative  is  spoiled  or  forget  to  turn  it  at  all. 

Practice  may  be  had  by  turning  the  camera  crank  without  film. 
The  length  of  exposure  is  dependent  upon  the  speed  of  the  crank. 
If  the  crank  is  turned  faster  as  it  comes  down,  the  exposure  will  be 
shorter  for  the  picture  made  then,  and  in  the  negative  every  fifth  or 
sixth  or  eighth  picture  will  be  under-exposed  as  compared  with  the 
remainder  of  the  negative.  Such  a  negative  cannot  be  used  because 
a  print  from  it  would  show  similar  variations  and  the  result  for  the 
audience  viewing  the  projected  picture  would  be  disagreeable. 

The  crank  must  be  turned  without  shaking  the  camera.  If 
the  operator  throws  liis  weight  upon  the  crank  in  any  part  of  the 
turn,  the  tripod  will  yield  slightly  and  change  the  view  in  the  film 
window  by  sliifting  it  slightly  up  or  down  or  sideways.  This  shift- 
ing will  occur  periodically  with  each  turn  of  the  crank  and  the 
result  is  a  strange  waving  or  surging  effect  in  the  projected  picture. 
To  turn  a  crank  uniformly  in  all  parts  of  its  revolution,  the  elbow 
may  be  placed  in  hne  with  the  center  of  the  crank  shaft  and  the 
crank  turned  with  a  movement  of  the  forearm  only,  keeping  the 
elbow  still.  In  this  way,  the  operator's  weight  is  not  thrown  upon 
the  crank  and  a  steady  rate  is  obtained. 

The  beginner  must  keep  his  eye  on  the  speed  gauge  until  turn- 
ing becomes  automatic.  If  there  is  no  speed  gauge,  the  best  plan 
is  to  count  while  turning,  and  not  to  look  at  all  at  the  action  in  the 
scene. 

Cameras  have  been  built  to  give  three,  four,  five,  six,  or  eight 
pictures  for  one  turn  of  the  crank.  Four,  six,  and  eight  are  in  com- 
mon use.  The  number  of  pictures,  not  the  number  of  turns  of  the 
crank,  is  the  end  desired,  and  this  means  different  crank  speeds  for 
different  cameras.  With  eight  pictures  per  turn — the  speed  most 
commonly  met  in  modern  professional  cameras — fourteen  pictures 
per  second  are  obtained  by  turning  the  crank  at  the  rate  of  105  turns 
per  minute;  at  six  pictures  per  turn  the  crank  speed  required  is 
140  turns  per  minute.  Many  watches  tick  five  ticks  per  second, 
300  ticks  per  minute.  Get  a  watch  ticking  300  per  minute  and 
learn  to  count  one-two-three,  one-two-three,  one-two-three,  just 
as  fast  as  the  watch  ticks,  turning  the  crank  one  turn  for  every  one- 
two-three,  and  the  crank  speed  will  be  one  hundred  turns  per  min- 


130 


MOTOGRAPHY  63 

ute,  which  is  near  the  proper  speed  for  an  eight-picture  camera. 
Count  one-two,  one-two,  one-two,  for  the  ticks  of  the  watch  and 
turn  the  crank  of  a  six-picture  camera  one  turn  for  each  one-two. 
Useful  practice  may  be  had  by  turning  the  crank  and  holding  the 
watch  to  the  ear,  a  plan  feasible  even  when  actually  taking  pictures 
in  the  field.  The  greatest  precautions  must  be  taken  by  the  new 
camera  man  to  prevent  the  action  of  the  scene  taking  his  atten- 
tion from  the  crank. 

When  the  trick  handle  is  used,  it  is  to  be  turned  at  the  same 
speed  as  the  main  handle,  as  though  the  full  number  of  pictures 
were  being  taken. 

To  secure  the  best  results  with  the  panoram  handle,  it  should 
be  operated  by  an  assistant,  but  with  practice  passable  results  may 
be  obtained  by  one  operator,  turning  the  picture  crank  with  one 
hand  while  he  turns  the  panoram  handle  at  a  different  rate  of  speed 
with  the  other  hand. 

Setting  up  Camera.  The  camera  must  be  rigid  upon  its  tripod, 
and  it  must  be  level.  A  level  may  be  built  into  the  camera  case,  or 
a  small  pocket  level  placed  upon  the  top  of  the  camera  will  serve, 
the  level  being  tried  both  crosswise  and  lengthwise  of  the  top  of 
the  camera.  To  "find"  the  view  properly  it  may  be  necessary  to 
tip  the  camera  front  up,  but  only  ludicrous  results  will  be  obtained 
when  the  camera  is  not  level  crosswise.  In  the  absence  of  a  level, 
step  back  a  few  feet  from  the  camera  and  "sight"  it  against  the 
horizon  line  or  some  neighboring  building.  It  is  almost  the  uni- 
versal rule  in  making  pictures  of  dramatic  action  with  natural  set- 
tings to  set  the  camera  upon  a  portable  platform  probably  4  feet 
high,  thus  bringing  the  lens  of  the  camera  above  the  heads  of  the 
actors  and  of  passers-by.  This  elevation  also  enables  the  camera 
man  to  arrange  his  image  with  the  horizon  line  above  the  top  line 
of  the  picture  and  thus  cut  out  any  signboards,  fences,  and  houses 
of  the  extreme  background. 

Lens  Length.  The  standard  length  for  moving  picture  lenses 
is  3  inches.  This  gives  an  angle  of  view  of  about  twenty  degrees; 
a  2-inch  lens  gives  an  angle  of  about  thirty  degrees.  The  camera 
must  include  in  its  film  window  as  much  of  the  scene  as  the  pro- 
ducer desires,  and  the  producer  must  know,  particularly  in  a  natural 
setting,  just  where  the  limit  lines  of  his  scene  are  located,  that  he 


131 


64  THE  MOTION  PICTURE 

may  keep  his  actors  in  the  film  window  when  they  are  supposed 
to  be  in  the  scene.  ^More  of  the  immediate  foreground  may  be  in- 
cluded in  the  film  window  image  by  moving  the  camera  stand  back, 
but  where  this  cannot  be  done  a  similar  result  may  be  had  by  sub- 
stituting the  2-inch  lens  for  the  regular  3-inch  lens.  \Mien  too  much 
of  the  foreground  is  included,  the  camera  may  be  moved  forward 
or  a  4-inch  lens  may  be  substituted.  The  camera  man  whose  camera 
has  but  one  lens  will  find  himself  at  his  wits  end  sometimes  to  include 
in  the  view  just  what  the  producer  wants  and  no  more.  The  most 
useful  lenses  are  the  standard  (3-inch)  and  the  "wide-angle"  (2- 
inch).  Lenses  of  5-inch  focus  or  longer  are  useful  only  in  travel 
work  for  taking  scenes  and  views  of  objects  which  cannot  be  ap- 
proached closely,  and  for  making  pictures  of  trick  or  spectacular 
nature.  Lenses  of  great  focal  length  will  require  extension  mount- 
ing tubes,  since  there  is  no  bellows  extension  for  the  increase  of 
distance  between  the  lens  and  the  film  window. 

Focusing.  The  motion-picture  camera  has  no  bellows,  but  is 
focused  by  sliding  the  lens  in  its  mount.  The  barrel  may  have  a 
rack  and  pinion  with  knob  for  racking  the  lens  in  and  out,  or  the 
lens  may  be  mounted  in  a  screw  flange  and  may  be  moved  back- 
ward and  forward  by  turning  the  lens  in  the  mount.  A  limited 
movement  only  is  thus  obtained  as  compared  with  the  movement 
of  the  bellows  of  a  fixed  camera;  but  in  the  motion-picture  camera 
the  very  short  focal  lengths  of  the  lenses  require  but  small  move- 
ment for  their  maximum  adjustment  for  focus. 

It  is  convenient  to  have  the  lens  mount  so  arranged  that  when 
the  lens  is  as  far  back  as  possible,  at  the  limit  of  its  motion,  it  is  in 
universal  focus  for  its  largest  or  most  commonly  used  aperture. 
By  "universal"  focus  is  meant  that  position  of  the  lens  in  which 
distant  objects  are  in  focus  upon  the  screen,  nearer  objects  being 
to  some  extent  blurred.  At  //16,  objects  from  the  extreme  distance 
and  up  to  30  feet  from  the  camera  are  all  in  focus  with  the  proper 
adjustment;  with //32,  objects  up  to  20  feet;  at //6.3,  objects  up  to 
100  feet.  The  lens  position  for  universal  focus  depends  upon  the 
diaphragm  stop  used. 

In  a  crude  camera  it  may  be  necessary  to  open  the  camera 
case  and  focus  by  looking  directly  upon  the  film  window.  The 
camera  should  have  a  focusing  window  for  enabling  the  operator 


132 


MOTOGRAPHY  65 

to  see  the  image  in  the  film  window  without  opening  the  camera. 
This  window  may  be  either  in  front  of  the  fihn  or  back  of  the  film, 
and  of  course  must  be  closed  after  focusing  to  prevent  leakage  of 
light  to  the  film  while  being  exposed  by  the  crank.  As  the  dis- 
tance from  the  focusing  peephole  to  the  image  in  the  film  window 
is  several  inches,  it  is  customary  to  have  a  lens  for  focusing  which 
both  enlarges  the  image,  making  accurate  focus  easier,  and  inverts 
the  image  so  that  the  view  is  seen  right  side  up. 

Focusing  may  be  done  either  upon  the  sensitive  film  which 
has  been  threaded  through  the  camera  mechanism,  or  a  piece  of  very 
thin  ground  glass  or  of  celluloid  which  has  had  its  surface  "ground" 
similar  to  ground  glass,  which  may  be  placed  in  the  film  window  for 
focusing,  being  removed  and  the  film  threaded  up  after  focusing. 
Particularly  for  work  in  a  city  street  is  it  desirable  for  the  operator 
to  set  up  his  camera,  get  his  field  and  focus,  and  be  ready  to  turn 
in  the  shortest  possible  interval,  and  particularly  for  such  work 
will  the  dead  stop  for  universal  focus  be  found  desirable. 

Control  of  Image.  Aside  from  lens  length  and  point  of  view, 
the  operator  has  the  sliding  lens  board,  the  equivalent  of  the  rising 
and  falling  front  of  the  fixed  camera.  The  short  focal  length  of 
the  lenses  used  requires  caution  in  using  the  sliding  lens  board, 
since  the  definition  of  the  image  is  sacrificed  when  the  center  field 
of  the  lens  is  not  used.  The  sliding  front  may  be  assisted  by  tipping 
the  camera  sHghtly  when  the  resulting  distortion  is  not  objectionable. 

The  camera  man's  most  powerful  element  of  control  of  image 
is  found  in  the  selection  of  the  point  of  view,  and  his  tactful  control 
of  the  producer  in  avoiding  objectionable  camera  positions  and  in 
obtaining  such  camera  stands  as  will  lend  some  pictorial  value  to 
the  images  of  the  film  window. 

Shutter.  The  disk  shutter  is  universal  for  cameras.  A  disk  of 
thin  sheet  metal  revolves  in  a  plane  between  the  lens  and  the  sensitive 
film  in  the  film  window.  An  opening  is  cut  in  the  shutter,  or  a  part 
of  the  disk  is  cut  away,  and  the  light  is  cut  off  from  the  film  by  the 
shutter  except  while  the  opening  is  passing  the  lens.  The  opening 
is   adjustable. 

Such  a  shutter  usually  is  made  of  two  half-disks  mounted  upon 
a  shutter  shaft;  by  setting  these  exactly  over  each  other,  the  shutter 
will  be  "half  open,  half  closed,"  or  by  adjusting  them  upon  each 


133 


66  THE  MOTION  PICTURE 

other  the  open  space  may  be  reduced  to  any  desired  fraction  of  the 
"open"  area.  Some  shutters  are  pro\aded  with  adjustments  whereby 
the  shutter  exposure  may  be  changed  while  the  camera  is  being 
turned.  This  is  objectionable  because  it  renders  the  shutter  more 
liable  to  getting  out  of  adjustment  accidentally. 

Exposure  Time.  The  usual  exposure  is  "three-eighths  open." 
^^^len  taking  pictures  at  the  rate  of  fourteen  per  second,  this  figures 
out  I  of  1/14  of  a  second,  1/37  second,  or  27/1000  second,  that  the 
lens  is  open.  The  photographer  experienced  with  shutter  efficiencies 
in  fixed  camera  work  may  note  that  tliis  is  an  actinic  value  and  not 
a  mechanical  value,  and  that  the  exposure  mechanically  is  corre- 
spondingly of  greater  value  than  the  figures  seem  to  show. 

One-thirty-seventh  of  a  second  actinic  value  is  much  more 
than  the  average  of  snap-shot  hand  camera  exposures.  It  is  a  longer 
exposure  than  would  be  possible  with  the  fixed  camera  for  moving 
objects  and  longer  than  is  customary  with  hand  cameras.  ^Moving 
objects  will  show  a  blur  in  the  negative;  when  projected  upon  the 
picture  screen,  the  blurred  object  of  one  image  will  fade  into  the 
same  blurred  object  in  a  difi^erent  position  in  the  next  image,  and 
smooth  motion  will  be  simulated,  the  object  becoming  sharp  again 
when   its   motion   becomes  slower. 

Exposure  Control.  The  time  or  length  of  exposure  being  fixed 
by  the  mechanical  Hmitations  of  the  art  of  the  motion  picture,  and 
the  negative  film  being  of  but  one  available  speed  or  sensitiveness,  the 
sole  means  remaining  to  the  camera  operator  for  adjusting  his  ex- 
posure value  is  the  diaphragm  stop.  If  the  light  is  poor,  the  stop 
must  be  opened,  and  if  the  stop  at  its  full  does  not  give  enough  light, 
the  picture  cannot  be  made  unless  by  "trick"  processes.  In  the 
matter  of  limiting  quantity  of  light,  however,  two  elements  come 
to  the  relief  of  the  motographer.  First,  because  the  negative  is  to 
be  used  for  printing  a  transparency,  a  negative  may  be  of  value 
which  would  be  useless  for  opaque  paper  prints;  and  second,  the 
motion  in  the  projected  film  picture  will  keep  the  attention  of  the 
spectator  on  the  high  lights  and  cause  him  to  overlook  the  lack  of 
detail  in  the  shadows.  Successful  motion  pictures  may  be  obtained 
from  exposures  so  low  in  light  value  that  nothing  but  failure  could 
result  with  the  fixed  camera. 

As  the  diaphragm  stop  is  the  only  variable  element  available 


134 


MOTOGRAPHY 


67 


to  the  motographer,  Table  I  has  been  prepared  giving  the  proper 
diaphragm  stop  for  each  day  and  hour  of  the  year,  Eastman  fihn 
(Watkins  250,  Wynne  111),  |  open,  14  pictures  per  second  (1/37 
second),  latitude  of  the  northern  part  of  the  United  States: 


TABLE  I 
Exposure  Chart 


Jan. 

Feb. 

Mar. 

Apr. 

May 
June 
July 

Aug. 

Sep. 

Oct. 

Nov. 

Dec. 

5  A  M. 

/.8 

6  A.M. 

//8 

//ll 

//16 

//ll 

//8 

7  A.M. 

//4 

//ll 

//16 

//22 

//22 

//22 

//16 

//ll 

//4 

//■I 

8  A.M. 

//ll 

//16 

//22 

//22 

//22 

//22 

//22 

//16 

//ll 

//u 

9  A.M. 

//16 

//22 

//22 

//32 

//32 

//32 

//22 

//22 

//16 

//16 

10  A.M. 

to 

2  P.M. 

//22 

//32 

//32 

//45 

//45 

//45 

//32 

//32 

//22 

//22 

3  P.M. 

//16 

//22 

//22 

//32 

//45 

//45 

//32 

//32 

//16 

//16 

4  P.M. 

//ll 

//16 

//22 

//22 

//32 

//32 

//22 

//16 

//ll 

//ll 

5  P.M. 

//4 

//u 

//16 

//22 

//22 

//22 

//16 

//ll 

//4 

//■I 

6  P.M. 

//8 

//ll 

//16 

//ll 

//8 

7  P.M. 

• 

//8 

' 

This  table  is  subject  to  all  of  the  corrections  given  for  the  ex- 
posure table  for  the  fixed  camera.  "Double  exposure"  for  the 
motion-picture  camera  means  only  the  next  larger  diaphragm  stop, 
that  is,  the  next  lower  number.  "Four  times  exposure"  means 
two  numbers  lower,  and  so  on,  each  lower  number  doubling  the 
exposure.  "Half  exposure"  means  the  next  stop  number  higher 
than  the  one  given  in  the  table.  If  a  ray  filter  be  used,  the  diaphragm 
stop  must  be  opened  to  compensate,  two  stop  numbers  lower  for  a 
"four  times"  filter,  one  stop  number  lower  for  a  "two  times"  filter, 
or  three  stop  numbers  lower  for  an  "eight  times"  filter. 

Eastman  film  is  orthochromatic,  and  gives  color  values  and 
cloud  effects  when  used  with  an  orange  ray  filter.  It  is  of  the  sensi- 
tiveness used  for  "speed  Kodaks,"  one  and  a  half  times  as  fast  as 
ordinary  Kodak  film,  and  twice  as  fast  as  a  Seeds  26x  dry  plate. 

In  addition  to  all  of  the  corrections  for  clouds  and  nature  of 
subject,  as  used  for  fixed  photography,  a  quarter  of  the  exposure 


135 


68  THE  IMOTION  PICTURE 

may  still  be  suflBcient  in  view  of  the  nature  of  the  motion  picture  and 
the  tendency  of  the  spectator  to  view  the  high  lights  of  the  moving 
objects  and  neglect  the  shadows. 

In  computing  an  exposure,  the  object  in  motion  is  the  center 
of  interest,  and  all  other  parts  of  the  picture  are  negligible.  For 
instance,  in  a  picture  of  an  airship  outlined  against  the  sky,  the 
sky  correction  (one-tenth  exposure)  is  correct  even  though  there 
are  foreground  objects;  when  the  picture  is  projected,  the  spectators 
will  look  at  the  airship,  not  at  the  foreground.  In  a  scene  where 
one  actor  occupies  the  center  of  the  stage  and  the  play  of  expression 
in  the  face  is  the  only  action  of  the  scene,  it  is  poor  motography 
to  over-expose  the  white  face  for  the  sake  of  getting  detail  in  the  half- 
lighted  studio  background  at  which  none  of  the  audience  is  looldng. 

Exposure  Meters.  The  exposure  meter  used  for  fixed-camera 
work  is  entirely  suitable  for  motion-camera  work,  the  speed  of  the 
motion-picture  film  being  taken  as  250  Watkins  or  111  Wynne. 
Two  further  points  must  be  borne  in  mind.  First,  that  the  1/37 
exposure  given  by  the  motion-picture  camera  with  its  3/'8-open 
shutter  working  at  fourteen  revolutions  per  second  is  full  actinic 
value  for  the  time,  the  equivalent  of  a  focal  plane  shutter  in  a  fixed 
camera,  and  much  greater  value  than  the  similar  schedule  of  the 
automatic  leaf  shutter  common  on  fixed  cameras.  Second,  that  the 
motion-picture  negative  will  stand  an  under-exposure  of  a  quarter 
exposure  or  even  less  than  that  and  yet  give  a  successful  print.  To 
judge  by  the  product  of  some  studios  and  factories,  the  manufac- 
turers prefer  their  films  that  way. 

In  using  the  Wynne  meter,  the  light  value  or  "actinometer  time" 
is  taken  in  seconds  and  the  number  of  seconds  thus  found  is  set  up 
opposite  the  plate  speed  number.  The  number  representing  the 
seconds  of  sun  time  is  found  upon  the  inner  scale  and  the  speed 
(111)  of  the  motion  film  is  found  on  the  outer  scale  of  the  meter. 
These  two  are  brought  together.  Now  opposite  the  exposure  to  be 
given,  read  the  diaphragm  stop  to  be  used.  The  exposure  1/37  is 
the  line  between  1/32  and  1/45.  In  the  illustration,  the  sun  time 
six  seconds  is  set  opposite  the  film  speed  111,  and  opposite  the  1/37 
exposure  line  is  read  a  diaphragm  stop  between  f/7  and  //8. 

In  using  the  Watkins  meter,  the  light  time  is  taken  in  seconds 
and  is  set  opposite  the  1/37  exposure;  opposite  the  film  speed  250 


136 


MOTOGRAPHY  69 

then  is  read  the  diaphragm  stop  to  be  used.  Thus,  when  a  light 
time  of  3  seconds  is  taken,  3  on  the  light  scale  is  set  between  1/32 
and  1/45  on  the  outer  ring  which  is  both  exposure  and  plate  speed 
scale.    Opposite  1/250  will  be  read  either  U.  S.  No.  8  or//ll. 

In  using  any  meter  in  the  field,  the  correction  for  the  nature 
of  the  subject,  and  for  the  allowable  or  desirable  under-exposure 
of  the  film,  is  always  to  be  made.  If  the  camera  man  should  find 
that  his  critics  or  "bosses,"  whosoever  they  may  be,  prefer  thin 
negatives  resulting  from  under-exposures,  the  film  speed  may  be 
taken  as  Wynne  256  or  Wynne  512  and  the  meter  scale  will  give 
directly  in  its  scale  reading  the  required  diaphragm  stop  with  the 
correction  for  under-exposure — as  compared  with  fixed  camera  work 
— as  desired. 

In  the  daylight  studio,  the  meter  will  show  the  value  of  the 
daylight  upon  the  scene  set,  and  will  give  the  stop  required.  If  the 
stop  required  is  larger  than  can  be  had  in  the  lens,  the  meter  will 
show  by  a  proper  interpretation  what  proportion  of  the  necessary 
light  is  had,  and  the  remaining  proportion  of  light  may  be  supplied 
by  lighting  a  partial  battery  of  lamps. 

In  the  artificially  lighted  studio  scene,  the  exposure  is  constant 
and  is  known  from  experience,  being  always  the  same,  day  or  night, 
scene  after  scene. 

The  exposure  value  for  a  scene  lighted  with  standard  Cooper- 
Hewitt  mercury-vapor  lamps  rated  at  700  candle-power  may  be 
calculated  according  to  the  following  formula: 

Take  the  average  distance  from  all  lamps  to  waist  height  of  an 
actor  standing  in  the  middle  of  the  scene  set,  measured  in  number  of 
feet.  Midtiply  this  number  by  itself,  divide  by  ten  times  the  number 
of  lamps,  and  the  qvxitient  is  the  correct  exposure  at  //16.  Thus, 
with  100  lamps  averaging  10  feet  from  the  middle  of  the  stage  setting, 
the  solution  is  10X10 -^  (10X100) -=  1/10  second  at //1 6,  or  1/40 
second  at//8.    Therefore,  for  such  a  setting,  stop//8  should  be  used. 

^Miere  the  light  is  insufficient,  it  is  possible  to  open  the  shutter 
of  the  camera  to  ^-open-2--closed,  thus  increasing  the  exposure  by 
one-third  of  its  light  value.  By  turning  the  camera  slowly,  the  ex- 
posure value  is  further  increased,  but  this  can  be  done  only  with 
the  result  of  speeding  up  the  resulting  action  when  the  print  is  pro- 
jected.   It  is  the  producer's  option,  not  the  camera  man's. 


137 


70  THE  MOTION  PICTURE 

Panoramic  %'iews  of  poorly  lighted  scenes  without  moving 
figures,  as  the  interior  of  churches,  court  yards,  statuary,  conserva- 
tories, etc.,  and  factories  with  the  machinery  motionless,  may  be 
made  by  lengthening  the  exposure  by  turning  slowly,  but  only  by 
the  most  skilful  actors  is  it  possible  to  put  any  lifelike  movement 
into  such  a  picture. 

Duplicate  Exposures.  Exposure  values  are  always  doubtful 
even  when  calculated  from  the  meter,  ^^^len  two  cameras  are 
working  side  by  side  to  make  duplicate  negatives  of  the  same  scene, 
it  is  well  to  have  the  diphragm  stop  of  one  camera  one  number 
or  even  two  numbers  above  the  other,  giving  the  developing  room 
a  better  chance  to  get  one  really  perfect  negatiAe  out  of  the  pair  of 
films.  Duplicate  exposures  upon  a  scene  are  made  for  several 
reasons : 

That  one  negative  may  he  held  in  reserve  in  case  of  accident  in  a 
printing  machine  or  elsewhere. 

That  two  exposures  may  be  available  in  case  of  accident  before 
or  during  development. 

That  one  negative  may  be  exported  for  printing  abroad. 

That  two  filtyis  may  be  exposed  as  assurance  against  accident  in 
one  of  the  cameras. 

That  cameras  of  different  makes  may  have  their  products  confused. 

Trick  Crank.  The  main  crank  gives  a  large  number  of  pictures 
per  second,  and  the  camera  operator  acquires  a  skill  in  turning  it 
which  enables  him  to  take  fourteen  pictures  per  second  with  great 
precision.  AMien  it  is  desired,  for  trick  picture  purposes,  to  take 
the  pictures  at  a  slow  speed — that  the  action  may  be  speeded  up  in 
projection — it  is  possible  to  turn  the  main  crank  at  half  speed, 
but  better  to  use  a  "trick"  crank,  which  the  camera  man  may  turn 
at  his  normal  accustomed  speed.  This  trick  crank  is  geared  down 
in  the  camera  and  gives  only  half  the  inside  speed,  or  less,  sometimes 
making  only  one  picture  per  turn  of  the  crank.  The  opening  in  the 
shutter  must  be  changed  accordingly,  half  the  opening  for  half  the 
picture  taking  speed,  in  order  that  the  exposure  time  of  1/37  second 
may  be  maintained.  Correction  by  the  diaphragm  is  possible,  but 
results  in  too  much  motion  in  the  object  if  rapidly  moving.  Where 
the  main  crank  is  detachable,  it  may  be  put  on  either  the  main  shatf 
or  the  trick  shaft  of  the  camera. 


138 


MOTOGRAPHY  71 

Reversing.  The  camera  may  reverse  the  action  in  three  methods, 
of  which  the  third  mentioned  is  the  usual  one  employed.  First, 
some  cameras  are  so  constructed  that  the  handle  may  be  turned 
backward  or  forward.  When  making  reversed  scene  with  such  a 
camera,  load  the  film  into  the  take-up  position  and  the  take-up  box 
into  the  feed  position,  then  change  the  take-up  belt  or  gears  to 
wind  upon  the  feed  spindle  position  which  now  is  reversing  take-up. 
Second,  mount  a  reversing  prism  in  front  of  the  camera  and  turn  as 
usual.  Third,  the  camera  is  provided  with  a  tripod  screw  or  socket 
in  the  top.  Turn  the  camera  top  down  on  the  tripod,  and  turn  as 
usual  except  that  the  crank  now  is  upon  the  opposite  side  of  the 
camera  from  that  to  which  the  operator  is  accustomed. 

Finders.  A  finder  for  focusing  is  not  convenient  for  deter- 
mining the  view  while  panoraming.  It  is  possible  to  panoram  accu- 
rately by  sighting  along  the  side  or  top  corner  of  the  camera,  par- 
ticularly when  two  operators  are  working  the  camera,  but  when  there 
is  but  one  and  he  stands  at  the  side  of  the  camera,  turning  two  cranks 
at  the  same  time,  a  finder  bringing  the  view  into  convenient  position 
will  be  an  advantage. 

Indicator.  A  film-measuring  device  w^orks  upon  the  constant 
feed  of  the  film  and  has  its  dial  outside.  The  indicator  can  be  reset 
by  the  operator.  The  operator  sets  the  hand  to  zero  when  loading 
the  camera,  and  the  hand  then  wdll  read  upon  the  scale  the  length  of 
film  turned  through.  Know^ing  the  length  put  into  the  camera  when 
loading,  the  operator  can  by  subtraction  know  the  length  still  remain- 
ing. When  not  enough  film  remains  for  the  next  scene,  the  camera 
must  be  reloaded,  the  lens  being  capped  and  the  film  "marked," 
and  the  remainder  of  the  film  wound  through  into  the  take-up  box 
before  opening  the  camera  to  reload. 

It  is  possible  to  make  the  dial  of  the  film  indicator  read  "remain- 
ing film"  instead  of  "used  film,"  the  operator  setting  the  hand  back- 
ward to  the  equivalent  of  the  film  length  when  loading  the  camera, 
and  the  hand  reading  upon  the  dial  at  all  times  just  the  amount  of 
film  remaining  as  the  hand  approaches  zero. 

Marker.  The  marker  is  a  push  button  or  pull  knob  on  the 
outside  of  the  camera,  and  usually  operated  to  punch  a  hole  in  the 
film  near  the  film  window.  Its  use  is  to  indicate  on  the  film  the  end 
of  a  scene.    For  the  benefit  of  the  developing  room,  a  "test  exposure" 


139 


72  THE  MOTION  PICTURE 

of  a  few  feet  of  film  is  made  before  beginning  the  taking  of  the  scene 
for  the  final  motion  picture  negative.  The  camera  is  set  up,  focused, 
and  closed  ready  for  use,  the  light-struck  leader  is  turned  off  into 
the  take-up  box,  and  then  several  turns  of  the  crank  are  given,  ex- 
posing a  dozen  feet  of  the  film  before  the  action  is  ready  to  begin. 
The  "marker"  then  is  operated  to  punch  a  hole  in  the  film,  or  two 
or  three  holes  with  single  picture  space  between  them.  The  scene 
then  is  taken.  In  the  developing  room,  the  leader  of  film  ahead  of 
the  marker  holes  may  be  cut  off  and  developed  to  learn  whether 
the  exposure  is  correctly  timed,  and  whether  regular  or  special  de- 
veloper shall  be  used  in  the  development  of  the  scene  of  the  film. 

^Mien  the  unused  film  in  the  camera  is  not  enough  to  cover  the 
length  of  scene  which  the  producer  is  about  to  enact  before  the 
camera,  the  marker  is  operated  again  and  the  remainder  of  the  film 
wound  through.  A  memorandum  of  the  number  of  feet  of  unex- 
posed film  is  sent  with  the  reel  when  it  goes  back  to  the  factory, 
that  length  is  measured  off  and  the  film  is  cut  at  the  marker  holes, 
thus  sa\4ng  the  unused  film. 

Bianchi  Camera.  This  camera  does  not  use  the  intermittent 
motion,  but  uses  a  continuously  moving  film  and  passes  the  rays  of 
the  image  through  a  revoh-ing  prism.  The  only  difference  to  the 
camera  operator  is  the  method  of  threading  up  the  film. 

Hamacek  Camera.  This  camera  uses  no  sprockets,  and  the 
film  is  not  perforated.  The  method  of  use  is  in  all  ways  similar  to 
the  camera  using  perforated  film,  except  in  the  detail  of  threading. 

No  matter  what  the  mechanism  of  the  camera,  the  operator 
should  understand  it  thoroughly,  and  keep  it  clean,  properly  oiled, 
and  in  perfect  adjustment  and  nmning  condition. 

Factory  Floor  Plan.  Fig.  15  shows  a  floor  plan  suitable  for  a 
small  motion-picture  film  factory.  This  shows  only  the  "photog- 
rapher's" department,  the  sales  offices  and  the  studio  being  adjacent 
or  elsewhere. 

The  plan  is  self-explanatory  outside  of  the  developing  room 
and  the  light-trap  entrance  to  the  developing  and  printing  rooms. 
The  perforating  room  is  entered  only  through  the  printing  room. 
Partitions  form  a  tortuous  pathway  into  the  developing  room  and 
printing  room  from  the  shipping  room,  permitting  the  free  access  to 
and  from  these  rooms  without  doors,  and  without  danger  of  accidental 


140 


MOTOGRAPHY 


73 


light  flashes  into  the  rooms  by  reason  of  the  opening  of  the  doors. 
At  the  end  of  the  developing  room  next  the  washing  room  a  large 
door  shown  double  is  of  sufficient  size  to  permit  a  developing  cage 
to  pass  through.  Because  of  the  opening  of  this  outer  door  to  the 
developing  room,  there  is  no  door  between  the  printing  room  and 
developing  room,  passage  being  had  through  the  entrance  passage- 
ways, or  by  a  turntable  in  the  partition. 

Development  of  Films.  Cages.  For  development,  the  exposed 
or  printed  film  is  wound  spirally  upon  cages  3  feet  in  diameter  and 
5  feet  long,  one  such  cage  taking  a  200-foot  roll  of  film.    The  ends 


■ 1                                                                                  1 

DEVEL0PIN6  ROOM        1                                                                         1 

PERIVPATIN6 

-.PPINTIN6 

1.                            WASHING                                   1 

/POOM 

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ROOM 

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2 

3 

4 

'                           6TAININ6  eo 
'                        60FTENIN6 
1                             ROOM 

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\ 

J 

JTORASe 

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\ 

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"-        — 

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DI?YIN6                                 1 

,                            '  ffOOM                                    1 

OFFICe 

IN5P5CTINe 
PACKING  ai 
5mPPIN6 
ROOM 

1 

Fig.   15.     A  Film  Factory  Floor  Flan 

of  the  cage  are  built  like  wheels  of  feUies  and  spokes,  the  ends  being 
connected  by  round  polished  wood  rods,  the  whole  appearing  like 
a  large  cylindrical  cage  with  an  axle  through  the  center. 

Trays.  The  developing  tray  is  of  wood,  6  inches  deep,  and 
has  within  it  a  zinc  trough  curved  with  the  curvature  of  the  develop- 
ing cage.  Standards  at  the  ends  of  the  developing  tray  take  the 
axles  of  the  developing  cage  and  support  its  surface  within  h  inch  of 
the  bottom  of  the  zinc  tray  which  it  fits  closely  but  does  not  touch, 
turning  freely  on.  its  axle.  A  few  gallons  of  developer  in  the  zinc 
tray  will  develop  several  cages  of  film,  the  cage  being  turned  con- 
stantly during  development.  The  wood  tray  catches  what  developer 
splashes  over  the  zinc. 


141 


74  THE  MOTION  PICTURE 

Trays  for  washing  do  not  have  the  inner  zinc  trough,  being 
filled  with  water,  running  water  if  convenient.  The  hypo  trays  also 
should  have  an  abundance  of  hypo  solution,  and  do  not  require  the 
inner  zinc  trough  for  economy  of  solution  as  is  the  case  with  the 
developer. 

Room.  Four  trays  are  shown  in  the  floor  plan,  No.  1  developer, 
No.  2  water.  No.  3  water,  and  No.  4  hypo  fixing  bath.  The  cages 
are  handled  by  the  developing  room  operator  and  an  assistant,  lift- 
ing at  the  two  ends  of  the  axle.  The  routine  of  development  is  as 
follows  : 

Developing.  Through  the  large  door,  a  developing  cage  is 
brought  in  and  hung  over  the  developing  tray  on  high  journals,  a 
few  inches  above  the  developer.  The  large  door  being  securely 
closed  and  the  room  lighted  by  red  light  only,  the  operator  opens 
a  tin  box  of  exposed  film,  attaches  one  end  with  a  clamp  to  one  of 
the  slats  of  the  cage,  at  one  end;  the  assistant  turns  the  cage  and  the 
operator  feeds  the  film  on  from  the  roll,  attaching  the  end  when  all 
is  fed  on.  The  cage  now  is  set  down  on  lower  journals  and  turned 
in  the  developer  by  the  assistant  while  the  operator  watches  the 
images  until  fully  developed.  The  cage  then  is  lifted  to  the  wash 
water  tray,  turned  a  few  times,  then  to  the  second  wash  water  and 
turned  a  few  times,  then  to  the  fixing  bath.  ^Mien  the  milkiness  is 
gone,  the  big  door  is  opened,  the  cage  with  the  wet  film  is  carried 
out  to  the  washing  room,  and  another  empty  cage  is  brought  in  and 
the  big  door  closed  again. 

Wofthing.  Two  assistants  in  the  washing  room  wash  the  film 
through  several  waters  or  in  running  water  to  free  it  from  hypo, 
then  turn  it  in  a  tray  of  diluted  glycerine — 1  part  glycerine,  33  parts 
water — for  a  minute  and  carry  it  into  the  drying  room. 

Drying.  The  drying  drums  differ  from  the  developing  drums 
in  having  smooth  surfaces  instead  of  being  cyhnders  of  slats.  Also, 
they  may  be  larger  than  the  developing  cages,  since  they  do  not  have 
to  be  handled — 4  feet  in  diameter  by  8  feet  long  is  reasonable,  and 
will  hold  600  feet  of  film.  Two  attendants  are  required  in  the  drying 
room.  The  end  of  the  film  is  attached  to  the  drum  with  a  thumb 
tack  and  one  attendant  turns  the  drum  by  hand,  while  the  other 
attendant  guides  the  wet  film  from  the  developing  cage  to  the  sur- 
face of  the  drying  drum.     When  the  end  is  reached,  it  is  attached 


142 


MOTOGRAPHY  75 

with  a  tack  or  push  pin,  and  the  drying  drum  is  belted  to  a  motor 
wliich  drives  it  continuously  until  the  film  is  dry.  The  developing 
drum  is  sent  back  to  the  washing  room  for  use  again  in  the  develop- 
ment of  films. 

When  films  are  dry,  they  are  unwound  from  the  drying  drums 
to  reels  or  into  baskets  and  taken  to  the  inspection  room,  if  positives, 
for  shipment,  or  sent  to  the  photographer  for  inspection  and  proofs, 
if  negatives. 

Making  Titles.  The  making  of  a  title  is  a  simple  case  of  the 
making  of  a  motion  picture  of  an  object  which  as  a  general  rule  is 
not  moving.  The  titles  are  set  up  and  properly  lighted  and  pho- 
tographed with  a  motion-picture  camera,  using  the  length  of  film 
called  for  by  the  synopsis.  Most  conveniently,  titles  are  prepared 
in  batches,  a  number  of  titles  being  photographed  upon  a  long  strip 
of  film  which  then  is  developed  in  the  usual  way  and  a  proof  print 
taken.  The  titles  then  are  cut  apart  and  spliced  into  the  motion 
scenes  as  required  for  the  complete  film  pictures. 

To  make  titles  with  movable  letters,  a  table  top  is  covered  with 
black  cloth  and  a  motion-picture  camera  is  permanently  mounted 
above  it  and  focused  upon  the  surface  of  the  table.  Lamps  are 
placed  around  the  table  for  lighting  the  title.  The  light  need  not  be 
excessively  bright,  as  the  camera  may  be  turned  slowly  and  with  a 
large  shutter  opening. 

Upon  the  table  top,  white  letters  are  arranged  to  form  a  title, 
the  title  is  photographed  by  turning  the  camera  above  the  table, 
and  the  letters  immediately  are  arranged  again  for  the  next  title. 
Letters  cut  by  dies  from  white  paper  may  be  bought  in  various  sizes, 
or  porcelain  letters,  such  as  are  used  for  signs  on  window  glass,  also 
are  obtainable  in  various  sizes  and  in  various  styles  of  lettering. 
Lines  upon  the  table  top  show  the  edges  of  the  field  of  the  camera 
and  within  the  lines  the  desired  title  is  formed,  arranging  the  letters 
of  each  line  against  a  straight  edge  which  is  removed  before  pho- 
tographing. 

The  table  top  is  a  convenient  means  for  copying  all  kinds  of 
titles,  merely  laying  the  title  upon  the  table,  if  the  suspended  camera 
is  arranged  so  that  it  can  be  moved  to  different  heights  to  provide 
for  different  enlargements  of  the  various  titles,  and  further  arranged 
so  that  it  can  be  focused  conveniently. 


143 


76  THE  MOTION  PICTURE 

In  photographing  either  a  yellow  telegraph  blank  printed  with 
black  ink  or  a  white  telegraph  blank  printed  with  blue  ink,  a  heavy 
yellow  ray  filter  should  be  used  over  the  lens  to  increase  the  contrast 
in  the  resultant  title. 

A  suggestion  for  the  photographing  of  titles  is  that  a  slow  film 
be  used  for  the  negative  instead  of  the  extremely  fast  sensitive  film 
used  for  the  motion  scenes,  since  a  slow  film  will  give  a  greater  con- 
trast in  the  resulting  titles. 

A  reversed  title  is  made  as  follows:  With  a  title  in  black  letters 
on  a  white  card,  photograph  the  title  and  develop  as  usual ;  this  nega- 
tive has  clear  letters  on  a  dense  background.  Make  a  reversed  print 
by  printing  with  the  celluloid  side  of  the  negative  against  the  gelatine 
side  of  the  printing  stock.  This  print  when  examined  will  have  its 
letters  reading  backward,  like  a  negative,  but  will  have  black  letters 
on  a  clear  background.  This  reversed  print  is  the  reversed  negative, 
to  be  spliced  in  with  the  negatives  of  the  motion  scenes  for  printing 
the  titles  for  the  finished  pictures,  the  printing  for  the  final  scenes 
being  gelatine  to  gelatine,  as  for  the  motion  scenes.  In  the  print, 
the  reversed  title  will  appear  with  clear  letters  upon  a  dense  back- 
ground, making  the  title  when  projected  show  white  letters  upon  a 
black   screen. 

Printing.  Room.  The  proper  location  for  the  printing  room 
is  between  the  perforating  room  and  the  developing  room,  as  shown 
in  the  floor  plan  of  Fig.  15,  with  entrances  into  both  perforating  and 
developing  rooms  as  conveniently  arranged  as  possible.  The  print- 
ing room  constantly  requires  supplies  of  perforated  film  from  the 
perforating  room,  and  constantly  supplies  the  developing  room  with 
printed  film  for  development.  The  connection  between  the  print- 
ing room  and  the  developing  room  is  particularly  close,  since  by 
immediate  development  of  the  film  after  printing  the  developing 
room  operator  may  be  able  to  note  errors  in  printing  which  might 
spoil  large  quantities  of  film  if  printed  far  in  advance  of  development. 
The  printing  room  is  provided  with  printing  machines  and  power 
to  drive  them. 

Machines.  Obviously,  a  negative  for  a  reel  of  film  1,000  feet 
long  cannot  well  be  handled  in  a  contact  printing  frame  such  as  is 
used  for  printing  the  negatives  from  a  fixed  camera,  nor  is  it  prac- 
ticable to  cut  the  negative  into  sufficiently  short  lengths  for  such 


144 


MOTOGRAPHY  77 

contact  printing  even  if  proper  results  could  be  obtained  in  that 
manner.  Since  the  standard  roll  of  film  furnished  by  the  makers 
of  the  raw  film  is  200  feet,  and  since  the  developing  cages  are  also 
of  a  size  to  handle  the  200-foot  rolls  of  fihn,  the  1,000-foot  negative 
is  cut  into  five  pieces  of  200  feet  each  and  the  200-foot  length  is  the 
standard  length  through  the  factory  up  to  the  time  for  splicing  together 
into  the  reel  for  shipment  to  the  film  exchange. 

The  printing  machines  are  of  two  types,  stepping  and  rotary. 
The  stepping  printing  machine  has  a  film  window  and  an  inter- 
mittent film  movement.  There  is  no  lens.  An  incandescent  lamp 
is  arranged  to  shine  upon  the  film  window,  being  adjustable  in  dis- 
tance from  the  window.  The  lamp  is  enclosed,  to  prevent  leakage 
of  white  Ught  into  the  printing  room,  and  the  film  window  is  backed 
with  ruby  glass  to  permit  the  operator  to  see  the  image  in  the  win- 
dow and  to  prevent  leakage  of  white  light.  A  framing  device  is  a 
desirable  feature  of  a  stepping  printing  machine,  and  a  necessity  if 
the  intermittent  film  movement  is  not  entirely  reliable.  A  project- 
ing motion  head  may  be  used  as  a  printing  machine,  or  in  the  case 
of  amateur  work  the  lens  may  be  removed  from  the  camera  and 
the  camera  may  be  used  as  a  stepping  printing  machine.  The  pro- 
jecting head  has  the  framing  device,  while  the  camera  has  not,  and 
either  requires  the  printing  lamp  with  its  adjustment  for  distance 
to  be  added,  after  removing  the  lens. 

Two  feed  reels  are  provided,  one  for  the  negative  and  one  for 
the  raw  positive  film  stock,  the  two  ends  being  started  through  the 
film  window  together,  film  sides  together  and  the  negative  next 
the  light,  so  the  light  shines  through  the  negative  upon  the  positive. 
The  shutter  remains  upon  the  machine.  The  operator  then  applies 
the  power  and  keeps  the  image  framed  in  the  film  window.  A  take- 
up  reel  rolls  up  the  printed  positive  film,  but  it  is  customary  to  run 
the  negative  into  an  open  basket  and  to  rewind  it  before  making  the 
next  print,  so  that  the  printing  always  proceeds  from  the  same  end 
of  the  negative.  The  stepping  machine  will  print  from  10  to  100 
feet  per  minute. 

The  continuous  printing  machine  is  much  faster  in  operation 
than  the  stepping  machine,  printing  from  40  to  500  feet  per  min- 
ute according  to  the  quality  of  the  negative,  but  the  greater  perfec- 
tion in  mechanism  required  renders  the  continuous  machine  difficult 


145 


78  THE  MOTION  PICTURE 

to  construct,  and  the  greater  accuracy  required  in  adjustment  and 
operation  sometimes  results  in  losses  of  film  not  encountered  with 
the  stepping  machines;  and  if  the  defective  film  be  not  discovered 
and  discarded,  then  the  manufacturer  is  giving  to  his  customers 
an  inferior  product,  which  is  the  worst  condition  of  all. 

In  the  continuous  machine,  the  two  films,  negative  and  positive, 
are  wound  with  a  steady  motion  from  the  feed  rolls  to  the  take-up 
rolls,  passing  together  in  contact  in  front  of  a  window  lighted  with  the 
printing  lamp.  This  sounds  very  easy,  but  the  slightest  slipping  of 
one  film  upon  the  other  will  produce  an  effect  upon  the  picture  screen 
when  projected  which  will  drive  a  spectator  to  insanity,  and  the  slight- 
est lack  of  registration  in  the  perforations  of  the  two  films  will  pro- 
duce the  undesirable  slipping. 

Exposure.  By  the  term  "exposure"  in  printing,  the  same  mean- 
ing is  conveyed  as  in  using  the  camera,  namely,  the  amount  of  light 
which  is  permitted  to  pass  to  the  sensitive  film.  In  the  printing 
machine  this  depends  upon  the  intensity  of  the  printing  light  in  the 
window,  the  size  of  the  window  or  shutter  opening,  and  the  speed 
at  which  the  printing  machine  is  driven. 

With  either  the  stepping  or  contiiuious  machine,  the  amount 
of  exposure  may  be  regulated  without  stopping  the  machine  by 
changing  the  distance  of  the  printing  lamp  from  the  film;  doubling 
the  distance  cuts  the  exposure  value  by  four;  and  dividing  the  print- 
ing-lamp distance  by  three,  multiplies  the  exposure  value  by  nine, 
according  to  the  law  of  squares. 

With  either  the  stepping  or  continuous  machine,  the  amount 
of  exposure  may  be  regulated  by  changing  the  speed  of  driving  the 
machine.  This  regulation  does  not  apply  the  law  of  squares  but 
gives  a  lineal  inverse  ratio  to  the  exposure,  half  the  speed  giving 
double  the  exposure,  double  the  speed  giving  half  the  exposure,  and 
so  on. 

With  the  stepping  machine,  the  opening  of  the  shutter  may 
be  changed  from  i-open  to  j-open  or  |-open,  the  change  in  exposure 
value  being  in  direct  ratio  to  the  size  of  the  open  portion  of  the  shut- 
ter. It  is  possible  to  construct  printing  machines  in  which  the  shutter 
opening  may  be  changed  without  stopping  the  machine,  inasmuch 
as  some  motion-picture  cameras  have  this  feature  in  the  shutter  and 
such  a  camera  shutter  may  be  used  in  a  stepping  printing  machine. 


146 


MOTOGRAPm^  79 

With  the  continuous  machine,  the  size  of  the  film  window  or 
slit  of  light  shining  upon  the  film  may  be  changed  without  stopping 
the  printing  machine.  The  printing  window  or  spot  of  light  which 
impresses  the  image  upon  the  positive  film  as  the  two  films  pass 
may  be  large  enough  to  cover  a  full  image,  or  two  images,  or  may  be 
only  a  quarter  of  an  inch  in  width,  or  even  narrower,  extending 
always  from  side  to  side  of  the  film.  The  narrower  this  band  of  light, 
the  less  injurious  to  the  resulting  print  wnll  be  any  lack  of  accuracy 
in  the  adjustment  of  the  printing  machine,  or  in  the  perforations  of 
the  two  films.  With  a  narrow  band  of  light,  the  printing  lamp  must 
be  nearer,  or  brighter,  or  the  speed  of  the  machine  must  be  slower. 
Incandescent  electric  lamps  are  used  because  of  the  uniformity 
of  their  illuminating  power. 

Film  Adjustment  During  Printing.  The  200-foot  piece  of 
negative  is  composed  likely  of  half  a  dozen  motion  scenes,  some 
inside  studio  work  and  some  outdoor  work,  interspersed  with  titles. 
That  all  these  short  negatives,  made  under  varying  conditions, 
should  have  the  same  printing  density  and  require  the  same  exposure 
in  the  printing  machine  is  quite  unlikely.  Each  200-foot  length  of 
negative  is  inspected  by  the  chief  photographer  and  ticketed  for 
exposure.  Following  is  a  sample  exposure  ticket  for  a  stepping 
printing  machine  having  lamp  distance  as  its  only  adjustment  w^hile 
moving. 

First  Negative,  "The  New  Boarder" 
Speed  25  feet  per  minute 
Shutter  |-open 
12'  title  3" 
30'  interior  scene  IC" 

6'  title  3" 
20'  interior  scene  10" 
10'  outside  scene  8" 
60'  interior  scene  10" 

6'  title  3" 
40'  outside  scene  G" 

The  number  of  feet  given  at  the  beginning  of  each  line  of  the 
ticket  indicates  the  length  of  film  which  is  taken  up  with  the  title 
or  scene,  that  the  printer  may  anticipate  the  instant  when  the  next 
change  is  to  be  made.  The  exact  instant  is  known  in  a  stepping 
machine  by  watching  the  images  of  the  negative  in  the  film  window. 
In  a  continuous  printing  machine,  the  images  are  blurred  by  the 


147 


80  THE  MOTION  PICTURE 

steady  motion,  but  the  change  in  density  of  the  negative  will  be 
noticed,  and  further  guidance  may  be  had  by  cutting  a  small  notch 
in  the  edge  of  the  negative  film  and  arranging  an  electric  circuit  to 
tap  a  bell  as  the  notch  passes. 

The  lamp  of  the  printing  machine  is  movable  by  a  lever  which 
is  provided  with  pointer  and  scale  and  with  movable  stops  which 
may  be  set  to  stop  the  lever  at  different  lamp  distances.  To  print 
the  negative  ticketed  according  to  the  specimen  ticket  given,  the 
printer  sets  stops  permanently  at  3"  and  10",  the  limiting  positions, 
holding  the  lever  against  the  stops  for  that  portion  of  the  negative 
for  which  those  stops  are  correct,  and  holding  the  pointer  on  the 
scale  at  the  proper  number  for  other  sections  of  the  negative. 

For  use  with  a  continuous  machine,  the  exposure  ticket  would 
give  at  the  head  the  film  speed  and  slot  width,  or  would  give  at  the 
head  the  speed  and  lamp  distance  and  then  give  the  slot  width  for 
each  portion  of  the  negative,  the  adjustment  being  made  by  slot  width 
rather  than  by  lamp  distance. 

Making  the  Exposure  Ticket.  By  experience,  the  photographer 
in  charge  can  judge  the  printing  exposure  required  by  looking  through 
the  negative,  or  comparing  it  with  standard  specimens.  The  first 
print  should  be  developed  promptly  and  inspected,  the  ticket  being 
changed  if  required.  In  case  of  doubt  before  printing,  the  negative 
may  be  run  through  the  printing  machine  under  known  conditions 
with  a  foot  of  positive  film,  this  foot  being  attached  to  the  develop- 
ing drum  with  tacks  while  a  roll  is  being  developed.  By  the  result- 
ing specimen  print,  the  proper  exposure  may  be  judged. 

Developing  Prints.  Processes  suitable  for  developing  lantern 
slide  plates  in  fixed  camera  photography  are  suitable  for  the  motion- 
picture  positive  prints.  Hydro-metol  or  hydro-quinone  developer 
are  usual.  The  positive  print  is  developed,  washed,  fixed,  washed, 
softened  in  glycerine,  and  dried. 

Inspection.  After  drying,  the  prints  are  carefully  looked  over, 
foot  by  fcot,  for  defects  of  any  character  whatever.  The  five  200- 
foot  pieces  of  each  1,000-foot  reel  then  are  spliced  together  in  proper 
order  and  the  reel  is  ready  for  packing  and  shipment.  Isolated 
defective  images  are  cut  out  and  a  splice  made.  AMiere  more  than 
a  limited  number  of  images  in  one  place  are  found  defective  in  the 
print,  the  place  is  marked  and  a  short  length  printed  from  the  negative 


148 


MOTOGRAPHY  81 

and  substituted  for  the  defective  length  of  film.  Hand  staining, 
hand  coloring,  and  hand  spotting  of  the  prints  are  done  in  the  inspec- 
tion department  unless  of  such  quantity  that  a  special  department 
is  created  for  the  work.  After  passing  the  inspection,  the  film  is 
packed  in  its  sheet  iron  shipping  cases,  one  reel  in  a  case,  and  sent 
to  the  storage  room  until  required  for  shipment. 

Print  Spotting.  Very  little  hand  work  is  done  upon  the  print 
after  it  is  dried,  but  sometimes  a  reel  of  negative  will  have  a  scene 
which  requires  hand  work  on  each  print  to  bring  it  up  to  the  standard 
of  the  factory,  or  to  make  it  passable  at  all.  If  the  scene  cannot  be 
retaken  to  secure  an  improved  negative,  the  hand  work  upon  the 
prints  must  be  done.  In  many  instances,  it  is  possible  to  balance  the 
cost  and  inconvenience  of  necessary  hand  work  upon  prints  or 
negative  against  the  cost  of  reproducing  the  scene  and  securing  an 
improved   negative. 

Staining.  Staining  of  a  print  is  done  in  the  wash-room  as  a 
part  of  the  washing  process,  and  is  done  in  the  same  manner  that  a 
laundress  uses  in  bluing  her  clothes.  The  last  rinse  water,  or  the 
glycerine  bath,  or  both,  are  charged  with  an  aniline  dye  or  other 
water-soluble  dye  stuff,  and  the  film  takes  the  color  in  passing  through 
the  baths.  This  produces  a  stained  gelatine  film  on  which  the  silver 
image  is  still  black.  \^Tien  projected  it  produces  a  black  picture 
upon  a  tinted  screen.  It  is  largely  used  for  reversed  titles,  producing 
the  title  in  tinted  letters  upon  a  black  picture  screen  and  giving  a 
more  pleasing  effect  than  a  plain  white  title.  The  Western  Union 
Telegraph  Company  uses  a  yellow  telegraph  blank,  and  titles  show- 
ing such  messages  sometimes  are  stained  yellow  to  lend  realism  to 
the  title. 

Toning  or  Monochroming.  In  the  toned  or  monochromed  film, 
the  gelatine  remains  clear  and  the  shadows  of  the  image  are  colored, 
giving  the  effect  upon  the  picture  screen  when  projected  of  a  picture 
painted  with  color  upon  a  white  sheet.  The  processes  may  be  classi- 
fied as  those  which  obtain  the  colored  image  in  the  first  development 
of  the  positive  film  and  those  which  obtain  the  color  by  subsequent 
manipulation. 

With  hydro-metol  or  hydro-quinone  developer  having  no  bromide 
or  insufficient  bromide,  the  image  will  come  up  in  olive  green.  Be- 
cause of  the  absence  of  bromide,  the  development  is  very  rapid 


149 


82  THE  MOTION  PICTURE 

and  difficult  to  control,  and  the  printing  exposure  must  be  corre- 
spondingly short  to  secure  a  good  print.  With  a  proper  adjust- 
ment of  printing  exposure,  developer  strength  and  bromide,  neutral 
blacks  can  be  secured.  With  a  developer  rich  in  bromide,  develop- 
ment is  slower  and  the  resulting  film  shows  shadows  tending  toward 
brown,  and  with  still  more  bromide  the  print  shows  purple  or  even 
red.  Printing  exposure  must  be  increased  to  avoid  unduly  prolonged 
development.  With  a  printing  exposure  of  ten  times  normal  for 
black  and  a  development  period  of  ten  times  normal  for  black  and 
with  sufficient  bromide  in  the  developer  to  restrain  the  development 
to  that  period  of  time  after  that  exposure,  the  resulting  images  will 
be  a  purple  which  tends  toward  red.  ^Nlonochroming  of  this  class 
is  done  in  the  developing  room,  before  the  print  is  passed  out  to  the 
daylight  washing  room. 

Processes  in  which  the  colored  image  is  not  obtained  in  the 
first  development  may  be  carried  on  in  the  daylight  washing  room, 
before  the  film  is  bathed  in  the  glycerine  bath.  Re-developing  for 
sepia,  and  intensification  and  toning  for  blue,  green,  and  red  may 
be  done  as  for  lantem-shde  plates.  The  literature  of  the  photographic 
art  is  amply  provided  with  formulas  for  these  processes. 

Repeater  Printing.  Where  it  is  desired  to  give  a  special  tone 
to  a  single  scene  or  short  portion  of  a  complete  film  picture,  the 
negative  for  that  scene  may  be  omitted  from  the  complete  negative, 
a  few  inches  of  blank  film  or  special  code  film  being  inserted  instead. 
The  short  scene  now  is  placed  in  the  printing  machine  and  the  two 
ends  stuck  together,  forming  a  belt.  A  200-foot  roll  of  positive  film 
is  started  through  the  printing  machine,  and  the  belt  of  negative  is 
printed  repeatedly  for  the  entire  length  of  the  positive  roll,  if  required, 
or  for  as  many  rolls  as  are  required.  A  large  number  of  repetitions 
of  a  short  scene  thus  may  be  developed  and  toned  at  once,  being 
cut  apart  after  drying  and  spliced  into  the  regular  prints  at  the 
proper  place,  the  bit  of  dummy  film  put  into  the  negative  acting  as 
a  guide  to  the  inspection  room  to  put  the  special  scene  in  its  proper 
place. 

Hand  Staining.  Titles  or  short  scenes  forming  parts  of  long 
pictures  and  re(|uiring  staining  may  be  done  more  conveniently  by 
staining  each  positive  print  with  a  brush,  by  hand,  than  by  special 
work  in  the  developing  or  washing  room  and  the  subsequent  splicing 


150 


MOTOGRAPHY  83 

required  in  the  inspecting  room.  One  of  the  desirable  features  of 
hand-staining  is  that  there  is  no  danger  of  errors  in  the  order  of 
scenes  in  sphcing  up,  since  the  sphcing  is  avoided.  The  slight 
unevenness  of  hand-staining  is  entirely  negligible  in  reversed  titles. 
Hand-staining  is  done  in  the  inspection  room  after  the  film  has  been 
dried. 

Coloring  Films.  Hand  Process.  The  primitive  method  is  to 
take  the  positive  film  and  a  set  of  brushes  and  water  colors  and 
color  each  of  the  small  images  as  though  they  were  so  many  separate 
and  distinct  photographs,  as  indeed  they  are.  In  connection  with 
this  method  of  hand-coloring  the  intermittent  mechanism  of  the 
camera  or  projecting  machine  may  be  used  with  great  convenience. 
The  strip  of  film  to  be  colored  is  arranged  over  a  glass  plate  through 
which  the  light  may  pass,  since  the  colorist  should  look  through  the 
film  to  get  the  effect  of  the  color.  A  leader  is  spliced  (or  pinned) 
to  the  film  to  be  colored  and  is  taken  through  an  intermittent  move- 
ment controlled  by  the  colorist's  foot  upon  a  pedal,  that  by  a  single 
pressure  upon  the  pedal  the  film  being  colored  may  be  stepped  for- 
ward one  picture.  This  change  will  take  place  very  quickly,  so  that 
the  colorist  seems  to  be  worldng  upon  the  same  image.  Taking 
the  blue  color  for  the  sky,  the  colorist  colors  the  sky  of  the  first  image, 
lifts  the  brush,  and  presses  the  shift  pedal,  proceeding  to  color  the 
sky  of  the  next  image  without  lifting  the  hand  from  the  position  of 
applying  the  color,  merely  lifting  the  brush  from  the  film  while 
shifting  the  images.  Having  colored  all  the  skies,  a  certain  tree, 
house,  or  chimney  is  colored  throughout  the  length  of  the  scene; 
then  the  moving  figures  are  colored,  the  brush  of  the  colorist  follow- 
ing the  figure  over  the  small  picture  as  the  figure  moves  in  the  action 
of  the  play.  Taken  in  connection  with  the  pedal  shift,  the  coloring 
of  some  film  scenes  becomes  surprisingly  rapid.  Hand-colored 
scenes  are  spliced  up  with  monochromed  and  stained  scenes  and 
titles.  A  "full  hand-colored  film"  picture  has  been  reported  by 
colorists  as  requiring  a  day's  labor  of  a  worker  for  each  35  feet  of 
film.  The  time  for  different  scenes  will  vary  widely,  and  this  35  feet 
per  day  may  be  taken  as  a  maximum  of  labor  in  hand-coloring. 

Stencil  Process.  A  stencil  is  made  for  each  color  to  be  applied 
to  the  film,  and  the  proper  colors  are  applied  through  the  stencils 
with  brushes  operated  by  hand.    Assuming  that  it  is  decided  to  color 


151 


84  THE  :\IOTION  PICTURE 

a  scene  with  three  colors,  red,  yellow,  and  blue:  Four  prints  of  the 
scene  are  taken  by  the  colorist;  upon  one  is  painted  with  red  all  of 
the  parts  of  each  image  which  are  to  be  colored  red  in  the  finished 
colored  picture,  just  as  the  hand  colorist  would  finish  with  the  red 
before  taking  up  another  color.  The  colorist  next  takes  the  yellow, 
but  takes  also  the  second  of  the  prints  and  colors  upon  the  second 
print  all  of  the  parts  which  are  to  be  colored  yellow  in  the  finished 
picture.  The  blue  color  and  the  third  of  the  prints  now  are  taken 
and  all  parts  to  be  blue  in  the  finished  picture  are  colored  blue  in  the 
third  film  print.  By  looking  through  all  three  of  the  prints  together, 
the  colorist  may  judge  what  the  result  of  the  combination  of  colors 
upon  one  print  will  be,  and  may  change  any  of  the  prints.  When 
finished,  there  are  three  colored  prints,  each  of  which  bears  but  a 
single  color.  If  more  than  three  colors  had  been  decided  upon  there 
would  be  more  than  three  of  the  partly  colored  prints.  The  three 
prints  now  are  cut  with  a  sharp  knife  or  with  stenciling  chisels,  re- 
moving all  of  the  colored  portions  and  leaving  all  of  the  uncolored 
portions.  The  result  is  a  set  of  stencils,  in  one  of  which  every  red 
spot  on  the  finished  colored  motion  film  is  indicated  by  a  hole  in 
the  stencil,  in  another  of  which  the  yellow  is  represented  similarly 
by  holes,  and  in  the  third  of  which  the  blue  is  represented  by  holes. 

The  fourth  print  of  the  scene  is  taken,  the  red  stencil  is  placed 
upon  it  and  a  brush  charged  with  red  ink  is  run  over  the  stencil. 
The  yellow  stencil  then  is  placed  upon  it  after  removing  the  red 
stencil  and  a  brush  charged  with  yellow  ink  is  run  over  it.  The 
yellow  stencil  being  removed,  the  blue  stencil  is  placed  upon  the  film 
and  a  brush  charged  with  blue  ink  is  run  over  it.  The  result  is  a  tri- 
color print  with  the  colors  stenciled  upon  the  black  lines  of  the 
photographic  print.  A  monochromed  or  stained  print  may  be  sten- 
ciled over  in  the  same  way,  producing  desired  effects. 

Machine  Process.  The  machine  feature  consists  of  the  appli- 
cation of  the  ink  through  the  stencil  by  a  stenciling  machine.  An 
illustration  from  the  published  American  patent  of  a  French  film 
coloring  machine  is  reproduced  in  Fig.  16.  The  method  of  making 
the  stencil  is  the  same  as  for  a  hand-stenciled  film.  The  operation 
is  as  follows:  Having  the  stencil  for  one  color,  and  the  film  to  be 
colored,  each  in  a  roll,  the  roll  of  stencil  is  placed  in  the  machine  at 
23  and  the  roll  of  film  to  be  colored  is  placed  at  24-    The  ends  then 


152 


MOTOGRAPHY 


85 


are  taken  through  the  guide  blocks  25,  the  stencil  band  being  shown 
by  the  dotted  line  2  and  the  film  to  be  colored  being  shown  by  the 
solid  Hne  3.  These  are  passed  together  over  the  large  roller  or  drum 
1.  Just  above  this  drum  there  is  a  short  endless  band  of  ribbon  21. 
This,  the  inventor  tells  us,  should  be  of  velvet,  so  that  it  offers  a 
soft  brushlike  surface  which  is  well  suited  to  pass  through  the  holes 
in  the  stencil  band  and  touch  the  film  to  be  colored,  which  lies  just 
underneath.  The  band  21,  which  is  really  an  ink  brush,  runs  over 
three  rollers,  and  runs  in  a  direction  opposite  to  the  direction  of 
the  film  and  stencil  band,  the  directions  of  the  movements  of  the 
parts  being  shown  by  the  arrows  close  to  the  different  bands;  thus 
there  is  a  considerable  brushing  effect  between  the  inking  band  and 


/:-> 


Fig.  16.     Film-Coloring  Machine 

the  film  to  be  colored  wherever  a  hole  in  the  stencil  band  permits 
the  brush  band  21  to  get  through  to  touch  the  film.  This  charges 
the  film  with  ink  or  dye,  coloring  it  in  every  spot  where  the  color  is 
desired,  that  is  to  say,  everywhere  that  a  hole  has  been  made  in 
making  the  stencil  band  2. 

The  supply  of  ink  is  taken  from  the  tank  30  and  is  carried  first 
upon  a  short  belt  27;  it  is  taken  from  the  belt  27  and  put  upon  the 
inking  ribbon  21  by  the  revolving  brush  26.  The  whole  device  is 
driven  by  a  belt  and  runs  continuously,  the  teeth  upon  the  drum 
1  keeping  the  stencil  band  and  the  film  to  be  colored  traveling  con- 
stantly at  the  same  speed,  and  keeping  them  always  in  register. 


153 


86  THE  MOTION  PICTURE 

As  in  hand  stenciling,  a  separate  stencil  is  required  for  each 
color,  and  the  film  to  be  colored  is  run  through  as  many  coloring 
machines,  each  having  a  different  stencil  and  a  different  color  of 
ink,  as  there  are  colors  in  the  finished  picture. 

Waterproofing.  The  picture  film  is  celluloid  upon  one  side, 
gelatine  upon  the  other.  The  celluloid  side  is  hard,  glossy,  water- 
resisting,  scratch-resisting,  dust-resisting,  but  the  gelatine  side  is 
easily  scratched,  collects  dust  in  the  scratches  and  sometimes  with- 
out them,  and  is  ruined  by  a  drop  of  water,  yet  requires  a  moist 
atmosphere  or  it  will  crack  by  becoming  too  dry  and  brittle. 
In  the  process  called  "waterproofing"  celluloid  or  a  similar  sub- 
stance in  solution  is  applied  over  the  gelatine  film,  strikes  through 
the  film  and  unites  with  the  celluloid  body,  forming  a  celluloid 
skin  over  the  delicate  film  and  imprisoning  the  gelatine  like 
the  ham  in  a  railroad  sandwich.  After  that  treatment,  both 
sides  of  the  picture  film  are  hard  and  scratch-resisting,  and  the 
film  may  be  washed  with  water  (by  special  machinery  for  the 
purpose)  to  remove  dirt.  At  the  same  time,  the  moisture  which 
made  the  film  flexible  is  imprisoned  with  the  gelatine  and  the 
film  remains  flexible.  The  process  is  patented.  Either  plain  or 
colored  films  may  be  waterproofed,  or  the  negatives  in  the  print- 
ing room.  The  proper  time  for  waterproofing  is  before  the  film  is 
shipped  for  use. 

Packing  Films  for  Shipment.  The  films  are  shipped  in  full  reels, 
or  1,000-foot  lengths,  wound  with  open  center  with  the  title  end  out. 
Each  reel  is  packed  in  a  circular,  flat  sheet-iron  can  and  then  in  a 
wood  box;  this  is  a  requirement  of  the  express  companies.  A  further 
requirement  is  regarding  a  danger  label,  which  must  be  printed  on 
red  paper  not  less  than  3  inches  square,  reading  as  follows:  "Moving 
picture  films  must  not  he  loaded  or  stored  near  a  radiator,  stove,  or 
other  source  of  heat."  The  reason  for  the  last  rule  is  that  celluloid 
when  warm  gives  off  explosive  vapors. 

Reclaiming  Waste.  Light-struck  films  develop  black,  and  these 
may  be  sold  to  film  exchanges  for  leaders.  The  punchings  from  the 
perforating  room  contain  silver,  and  this  may  be  reclaimed  at  a  profit 
by  a  chemical  process.  The  black  silver  in  junk  or  spoiled  film  may 
be  reclaimed  but  usually  is  not,  and  the  same  is  true  of  the  silver  in 
the  used  hypo  bath. 


154 


SCENE  FROM  PHOTOPLAY,   "THE  INHERITANCE" 

Courtesy  of   Thomas  A.  Edison,  Inc.,  Orange,   IV.  J. 


MOTOGRAPHY  87 

PHOTOGRAPHIC    EQUIPMENT 

All  supplies  needed  by  the  manufacturer,  other  than  cameras, 
printing  machines,  perforating  machines,  and  film  stock,  may  be 
bought  in  any  city  in  the  open  market. 

Buying  Cameras.  Urban  and  other  English  and  French  cameras 
may  be  purchased  and  imported  into  the  United  States  at  costs 
ranging  from  $300  to  $400;  printing  machines  cost  about  the  same 
prices  as  cameras,  for  either  the  stepping  or  continuous  move- 
ment. The  importation  or  manufacture  of  cameras  in  the  United 
States  is  influenced  by  the  patent  situation.  Cameras  have  been 
offered  for  sale  in  the  United  States  at  prices  quoted  from  $475 
to  $2,500. 

Making  Cameras.  A  projecting  machine  may  be  converted 
into  a  camera,  though  rather  bulky  for  field  work  and  requiring  some 
ingenuity  to  accomplish  all  the  desired  features  of  a  camera  for 
both  studio  and  field  work.  A  projecting  machine  with  lens  removed 
and  a  hooded  lamp  at  the  aperture  becomes  a  printing  machine 
almost  without  change.  The  pin  or  claw  intermittent  movement 
is  preferable  to  the  sprocket  for  cameras. 

Buying  Films.  Several  prominent  makers  of  roll  films  for 
hand  cameras  have  taken  up  the  manufacture  of  film  for  motion- 
picture  cameras  and  are  supplying  the  market.  The  price  charged 
is  about  four  cents  per  foot,  unperforated.  From  some  dealers  it 
may  be  bought  perforated. 

Fire  Risk  in  Storing  Films.  A  rolled  film  in  its  tin  box  is  a  per- 
fectly safe  proposition  at  ordinary  temperatures.  The  celluloid 
body  of  the  film,  whether  raw  film,  prints,  or  junk,  gives  off  an  in- 
flammable and  explosive  gas,  giving  it  off  more  rapidly  when  warm 
than  when  cold.  A  vault  for  storing  films  must  have  a  vent;  a  slow 
but  continuous  draught  of  air  through  the  vault  seems  a  logical  pro- 
vision for  safety. 

CHRONOPHOTOQRAPHY 

The  requirement  for  scientific  study  usually  is  a  clear  sharp 
picture  taken  at  regular  intervals.  The  intervals  may  be  short  or 
long,  either  at  the  rate  of  several  hundred  pictures  per  second  or  at 
the  rate  of  one  picture  per  hour,  or  one  per  day.  The  results  occasion- 
ally are  of  interest  to  the  general  public. 


155 


88  THE  INIOTIOX  PICTURE 

Motographic  Microscopy.  The  image  of  the  thing  to  be  moto- 
graphed  is  taken  through  microscopic  lenses  to  the  motion  camera 
in  a  manner  easily  accomplished  when  the  lenses  are  available.  The 
greatest  difficulty  is  found  in  illuminating  the  subject  sufficiently  to 
achieve  the  short  motographic  exposure  without  destroying  the 
subject  by  the  heat  of  the  source  of  light.  By  carrying  the  light 
through  water  or  an  alum  cell  before  it  reaches  the  subject,  and  by 
operating  a  shutter  between  the  light  and  the  subject  so  that  the  light 
is  cut  off  from  the  subject  except  while  the  exposure  is  being  made, 
such  relief  from  the  heat  may  be  attained  as  will  permit  making  a 
motographic    picture    without    destroying    the    thing    motographed. 

Motographic  L  Itramicroscopy.  Ultramicroscopy  is  the  name 
given  to  the  process  of  microscopic  study  which  makes  use  of  the 
ultra-violet  (invisible)  rays,  recording  the  image  upon  a  photographic 
plate  and  studying  it  after  development.  Motographic  film  has  been 
operated  successfully  with  this  class  of  microscopic  study. 

X=Ray  Motograpliy.  The  invisible  X-ray  penetrates  many 
solids  which  are  impenetrable  by  light,  and  the  X-ray  is  able  to 
influence  the  photographic  dry  plate  or  motographic  film.  Passing 
through  the  body,  the  X-ray  is  obstructed  by  the  bones  and  the 
heavier  and  denser  organs,  throwing  a  shadow  of  them  upon  the 
photographic  surface.  By  arranging  the  motographic  camera  with 
proper  shutter  and  protective  X-opaque  shields  for  the  reels  and 
film,  motion  pictures  of  the  heart  in  action,  of  circulation  of  the  blood, 
etc.,  are  possible. 

TRICK  PICTURES 

There  is  no  standard  "box  of  tricks"  beyond  which  lies  nothing 
of  interest.  The  interest  never  ceases  when  trick-picture  making 
has  been  begun.  This  subject  was  opened  under  the  discussion 
of  tricks  in  the  production  of  the  specimen  film,  "High-Jumping 
Johnnie."  The  thoughts  there  given  were  but  the  simplest  of  tricks, 
easily  understood  or  almost  guessed  by  the  audience  in  watching 
the  picture.  In  addition  to  the  tricks  used  so  much  that  they  may 
be  considered  standard  illusions  in  motography,  special  effects  may 
be  attained  by  tricks  as  subtle  as  those  of  the  accomplished  magician 
before  his  audience.  A  few  of  the  standard  tricks  of  illusion  are 
here  described. 


156 


MOTOGRAPHY  89 

Reversals.  The  method  is  to  show  upon  the  screen  the  series 
in  the  order  just  reversing  the  order  in  which  the  pictures  were  taken. 
When  this  is  done,  all  the  characters  would  walk  backward,  objects 
would  fall  from  the  floor  upward  to  the  shelves  and  table,  smoke 
would  float  do^Ti  into  the  chimney,  etc. 

Means.  Turn  the  camera  bottom  up  on  the  tripod — by  a  tripod 
socket  in  the  top  of  the  box — this  will  reverse  tlie  action.  Or  print 
by  a  special  printing  machine  which  steps  the  film  negative  in  one 
direction  and  the  positive  stock  in  the  other  direction. 

Effects.  A  nmaway  horse  may  run  backward  and  push  the 
wagon  before  him  just  as  easily  as  running  forward  if  there  are  no 
people  on  the  street  who  also  would  walk  backward  and  thus  reverse 
the  illusion. 

A  witch  desires  to  create  money  from  a  piece  of  tallow  candle. 
She  melts  the  candle  and  pours  it  on  a  surface  to  cool.  From  this 
point  a  picture  of  coin  casts  in  tallow  melting  on  the  same  surface  is 
inserted  reversed,  giving  the  appearance  that  the  melted  tallow 
magically  takes  the  form  of  coins  and  hardens.  The  witch  then  ap- 
parently picks  them  off  as  good  coins  magically  created. 

A  sculptor  makes  a  wonderful  statue  in  record  time,  with  a 
wealth  of  detail,  by  skilfully  pulHng  apart  a  clay  model  before  the 
camera,  the  film  then  being  run  reversed  whereby  he  seems  to  build 
up,  not  to  tear  down. 

A  swimmer,  having  jumped  into  the  water,  by  a  reversed  film 
jumps  just  as  easily  out  again,  landing  safely  upon  the  bank,  pier, 
or  springboard,  feet  first,  every  time. 

Speed  Pictures.  AMien  pictures  are  taken  slowly  and  projected 
at  the  standard  rate,  the  action  of  the  picture  seems  correspondingly 
faster. 

Means.  Reduce  the  shutter  opening  and  turn  the  handle  slowly, 
or  turn  the  camera  mechanism,  by  a  specially  provided  gear  to  a 
special  handle  or  shaft  called  the  "trick  handle." 

Effects.  Chases  may  be  made  to  appear  much  more  rapid  than 
they  really  are,  and  acrobatic  actions  on  the  part  of  a  comedian  in 
the  scene  may  be  made  so  violent  as  to  be  ludicrous.  The  ordinary 
traffic  of  a  street  may  be  thus  speeded  up. 

Dummies.  "\Mien  a  character  is  required  by  the  plot  of  the 
picture  to  pass  through  some  hazardous  experience,  such  as  having 


157 


90  THE  MOTION  PICTURE 

his  head  cut  off  or  falling  from  a  high  building,  a  dummy  is  sub- 
stituted. 

Means.  The  action  having  progressed  to  the  point  where  the 
substitution  of  the  dummy  is  necessary  or  convenient,  the  producer 
cries  "Hold  it,"  or  "Freeze,"  and  all  actors  instantly  become  motion- 
less and  remain  so,  the  camera  man  stops  turning,  the  actor  to  be 
dummied  gets  off  the  scene,  the  producer  and  his  assistants  arrange 
the  dummy  figure  where  the  actor  was,  the  camera  man  is  given  the 
signal  to  turn,  the  remaining  actors  are  given  the  signal  to  go  on 
with  the  action  until  it  is  required  to  replace  the  dummy  with  the 
actor,  when  the  same  plan  of  freezing  over  the  change  is  carried  on. 
^Mien  the  film  is  developed  a  short  length  may  be  cut  out  at  each  of 
the  freezes  if  need  be  to  improve  the  picture. 

Effects.  An  accident  frequently  is  a  part  of  the  plot  of  the 
picture.  The  dummy  substitute  may  be  used  to  relieve  the  actor 
from  danger  in  that  scene.  The  film  picture  story  says  that  the  hero 
rushes  to  the  rail  of  an  ocean  liner  in  mid-ocean,  hurls  himself  over- 
board and  swims  to  shore.  The  picture  is  made  by  his  rushing  to 
the  rail,  picking  up  a  dummy  of  himself  and  throwing  it  overboard, 
while  the  photographer  or  producer  cuts  out  that  part  of  the  film 
where  he  picks  up  the  dummy  and  lifts  it  above  the  rail.  The  swnm 
to  shore  and  the  landing  on  the  distant  beach  is  made  in  the  tank 
in  the  studio  backyard. 

Ghosts.  Apparitions  are  made  by  exposing  the  negative  film 
twice  before  developing  it. 

Means.  A  lens  with  an  iris  diaphragm  so  that  it  may  be  opened 
and  closed  gradually  while  the  camera  is  running.  The  full  picture 
having  been  made,  the  ghost  is  staged  upon  a  stage  set  all  in  black 
and  the  film  already  exposed  is  run  through  the  camera  again  as 
noted  in  advance,  so  many  feet  with  the  lens  closed,  then  gradually 
opening  the  diaphragm  to  about  one-tenth  of  a  normal  exposure 
continuing  for  so  many  feet  and  gradually  closing  if  the  ghost  is  to 
fade  away,  but  suddenly  capping  the  lens  if  the  ghost  is  to  vanish 
instantaneously. 

Effects.  Only  white  or  light  figures  may  be  brought  into  the 
picture  in  this  way.  The  good  white  fairy  may  appear  thus  to  wave 
a  signal  to  the  favored  hero..  A  fairy  symbol  may  appear  upon  the 
wall  of  the  room  and  disappear.     The  actor  may  lie  dowTi  to  sleep 


158 


MOTOGRAPHY  91 

and   upon   a  blank  wall  (left   blank   for  the  purpose  in  th^  scene 
setting)  appears  the  action  of  his  dream. 

When  the  actor  thus  appearing  under  the  ghost  effect  is  required 
to  take  an  active  part  in  the  play  subsequently,  or  when  the  figure 
thus  to  be  produced  is  not  white  or  substantially  so,  then  the  illusion 
may  be  made  under  the  plan  for  dissolving  views. 

Dissolving  Views.  ^Mien  it  is  desired  to  have  an  actor  appear 
in  magical  manner  slowly  and  to  take  a  part  in  the  action  thereafter, 
the  producer  causes  the  actors  to  freeze,  and  the  camera  man  reduces 
his  aperture  gradually  to  a  closed  shutter.  The  camera  man  turns 
his  camera  back  to  the  point  where  he  began  to  close,  the  actor  to 
be  produced  takes  his  position  and  the  camera  man  begins  to  turn 
and  gradually  opens  his  shutter  diaphragm;  when  the  diaphragm 
is  nearly  open  the  action  may  proceed.  INIuch  practice  on  the  part 
of  the  camera  man,  or.  a  special  camera  with  automatic  diaphragm 
is  required.  Disappearance  of  any  character  is  effected  in  the  same 
manner. 

DouWe  Printing.  Apparitions  may  be  produced  by  making 
the  two  exposures  upon  separate  films  and  running  the  two  negatives 
through  the  printing  machine  together  with  the  printing  stock,  so 
that  the  images  of  both  the  negatives  are  impressed  upon  the  sensi- 
tive print  stock. 

AMiere  the  object  to  be  added  to  the  scene  is  a  dark  object  to 
be  added  in  a  light  area  of  the  original  scene,  it  is  added  by  running 
the  printing  stock  through  the  printing  machine  v/ith  the  first  nega- 
tive and  again  with  the  second  negative,  separately. 

^Mien  a  satisfactory  print  has  been  produced  by  the  double 
printing  process,  the  print  is  copied  upon  another  strip  of  film  stock, 
thus  producing  a  single  negative  of  the  double  print,  from  which 
single  negative  as  many  double-printed  positives  as  may  be  desired 
may  be  had,  with  less  trouble  than  maldng  the  total  number  of  double 
prints. 

Double  Exposures.  The  making  of  ghosts  by  double  exposures 
has  been  discussed.  An  explosion  in  the  midst  of  a  number  of  men 
may  be  made  by  making  an  exposure  of  many  feet  of  film  in  which 
at  a  given  signal  the  men  all  aci  upon  the  cue  that  the  explosion 
has  occurred.  The  camera  man  then  goes  to  a  black  backe;roimd, 
having  noted  the  place  in  the  film  at  which  the  explosion  cue  occurred, 


159 


02  THE  IMOTIOX  PICTURE 

and  runs  the  film  from  that  point  upon  an  explosion  which  produces 
a  large  amount  of  white  smoke.  In  the  projected  picture,  the  men 
will  be  seen  enveloped  in  the  smoke  of  the  explosion,  which  did  not 
occur  perhaps  until  next  day.  This  effect  might  be  made  double  by 
printing  with  the  negatives  together. 

It  is  desired  to  photograph  the  semblance  of  an  actress  swimming 
in  deep  water,  presumably  at  the  bottom  of  the  sea.  An  aquarium 
is  photographed,  or  an  aquatic  background  scene  is  photographed 
upon  the  motion  film.  The  actress  then  is  attired  in  light  color, 
the  camera  is  attached  near  the  ceiling  or  mounted  in  the  rafters, 
the  actress  lies  upon  the  studio  floor  and  simulates  the  movements 
of  swimming.  In  the  finished  picture  she  is  seen  swimming  among 
the  details  of  the  aquarium  or  aquatic  background  scene. 

Mirrors.  The  appearance  of  a  character  in  a  scene  may  be 
effected  by  a  mirror  upon  the  stage,  the  actor  standing  off  the  stage 
but  in  view  of  the  camera  through  the  mirror  at  all  times,  appearing 
in  the  picture  according  to  the  amount  of  light  which  he  receives 
from  lamps  near  him.  ^^'hen  lighted  he  is  seen  in  the  play;  when 
darkened,  he  is  not  seen. 

By  mirrors  also  the  effect  of  diminutive  characters  upon  the 
stage  may  be  effected.  A  table  is  backed  by  a  nu'rror  which  is  not 
noted  except  as  a  part  of  the  paneled  wall.  In  the  mirror  is  visible  an 
actor  who  really  stands  beside  the  camera.  Owing  to  the  greater 
distance  of  this  reflected  actor  from  the  camera,  he  will  appear  of 
shorter  stature  than  those  actors  who  are  viewed  directly  by  the 
camera  without  reflection.  Thus  a  fairy  of  diminutive  size  may  be 
made  to  appear. 

The  secret  of  success  in  this  illusion  rests  upon  the  accuracy 
with  which  the  reflected  image  is  placed  in  the  picture,  and  upcn 
keeping  out  of  the  picture  any  intermediate  objects  between  the 
reflected  actor  and  the  directly  photographed  parts  of  the  picture. 

Such  a  picture  may  be  made  by  double  exposure,  by  double 
printing,  l)y  mirror,  or  l)y  blackroom  methods. 

Blackroom.  In  making  a  negative  of  a  single  figure  which  is 
to  be  printed  in  with  another  scene,  or  in  making  the  second  ex- 
posure of  a  double  exposure,  the  stage  is  hung  in  black  or  non-actinic 
color  value. 

With  a  black  stage,  the  distances  of  all  objects  on  the  stage 


160 


MOTOGRAPHY  93 

are  deprived  of  their  perspective  values  since  all  connecting  features 
of  the  stage  are  invisible  photographically.  A  man  sits  at  a  table 
near  the  camera.  The  camera  lens  is  level  with  the  table  top.  Upon 
the  distant  side  of  the  room  a  girl  is  dancing  upon  a  black  platform 
of  the  height  of  the  table.  To  the  eye  of  the  camera,  the  dancer's 
feet  just  touch  the  table  top,  but  because  of  her  distance  the  image 
is  proportionately  smaller  than  that  of  the  man.  The  resulting 
picture  shows  the  man  sitting  at  a  table  upon  the  top  of  which  is 
dancing  a  fairy  no  more  than  ten  inches  tall. 

Stop  Picture.  The  dummy  picture  is  called  a  stop  picture  be- 
cause the  camera  is  stopped  while  the  dummy  substitution  is  made. 
Pictures  in  which  sudden  appearances  and  disappearances  are  made, 
are  called  stop  pictures  because  the  camera  is  stopped  while  the 
actors  remain  frozen.  There  is  another  type  of  stop  picture  to  which 
the  name  is  particularly  applicable,  the  camera  being  stopped  after 
every  exposure. 

Means.  A  camera  making  one  exposure  with  one  turn  of  the 
handle,  and  which  may  be  left  always  with  its  shutter  closed  by  leav- 
ing the  handle  in  a  latched  position. 

Effects.  By  the  stop  picture  it  is  possible  to  give  inanimate  objects 
the  appearance  of  life.  Dolls  are  made  to  walk.  Toy  animals  of 
the  "humpty-dumpty"  type  are  made  to  perform  circus  feats.  Saws 
are  made  to  cut  off  boards  without  hands;  hammers  are  made  to 
drive  nails  without  hands;  shoe  laces  tie  themselves,  etc. 

Method.  The  stage  being  set,  the  handle  is  turned  once  on  the 
camera,  making  one  picture,  or  perhaps  several  at  the  beginning 
before  starting  the  action.  The  handle  being  left  in  its  latched 
position,  with  the  shutter  of  the  lens  closed,  the  moving  object  of 
the  stage  setting  is  moved  slightly.  If  a  box  of  matches  upo;i  a 
table  top  is  the  subject  of  the  picture,  the  inner  box  is  pushed  from 
the  cover  a  sixteenth  of  an  inch.  The  handle  of  the  camera  is  turned 
once.  The  inner  box  is  pushed  an  eighth  of  an  inch;  the  handle  is 
turned  again.  The  inner  box  is  pushed  another  eighth  and  the 
handle  is  turned  again,  the  person  or  the  hand  which  moved  the 
match  box  having  been  safely  out  of  the  field  of  the  camera  before 
the  crank  was  turned.  The  box  b^nng  opened  a  little  farther  and  a 
little  farther  each  time  soon  is  far  enough  open  to  permit  the  matches 
to  be  extracted.  One  match  raises  one  end  to  the  edge  of  the  box;  the 


161 


94  THE  MOTION  PICTURE 

handle  is  turned  once.  The  match  is  advanced  a  sixteenth  of  an  inch 
and  the  handle  is  turned  again;  another  sixteenth,  and  another, 
and  the  handle  may  be  turned  several  times  without  moving  the 
match,  giving  the  match  the  appearance  of  having  paused  in  its 
motion  to  obser^^e  whether  it  is  being  watched  in  its  escape  from 
the  box.  Careful  study  of  the  extent  of  each  motion  of  the  match 
and  the  direction,  and  the  taking  occasionally  of  more  than  one 
picture  between  moves  makes  it  possible  to  give  to  an  inanimate 
object  a  wonderful  simulation  of  life. 

This  class  of  stop  pictures  take  unlimited  time.  Perhaps  it  is 
a  job  for  rainy  days  in  the  studio. 

Film  manufacturers  are  permitting  the  popularity  of  trick  pic- 
tures to  decline  because  of  the  expense  of  producing  them.  The 
time  consumed  overbalances  all  features  of  apparent  economy  over 
ordinary  methods  for  producing  the  legitimate  motion  picture. 


162 


O   £g 

^  Is 

CO   S^ 

w  c;  ■ 

-)  =o 

O  '-;^ 
X  ^^ 

w  ^  s 

X    -^ 

Ha? 

w    _^ 

=  o 

->    =  :„ 

Jiff 

Moo 


MOTION-PICTURE  THEATER 

MANAGEMENT 

It  is  stating  a  platitude,  to  say  that  a  motion-picture  theater 
will  not  operate  itself  at  a  profit.  If  such  a  condition  ever  existed, 
competition  and  the  multiplication  of  theaters  has  eliminated  it 
from  the  ordinary,  and  has  made  such  instances  rare,  if  not  obsolete. 
Picture  theaters  from  time  to  time  close  their  doors  and  go  out  of 
business  because  they  do  not  pay  a  profit,  and  others  "change  hands" 
because  the  manager  has  found  that  he  is  making  less  money  operat- 
ing the  theater  than  he  could  make  doing  something  else.  If  the 
theater  would  only  "operate  itself"  and  pay  a  profit  merely  by  the 
condition  of  its  existence,  the  manager  might  be  a  negligible  quan- 
tity in  the  picture  theater,  and  his  personality,  his  duties,  his  special 
training,  and  the  limitations  of  his  business  might  be  neglected  in  a 
book  of  instruction  whose  scope  is  to  cover  the  entire  motion-picture 
industry. 

The  "Sick"  Motion=Picture  Theater.  A  picture  theater  is  giving 
service  to  the  citizens  of  a  district  of  the  city,  conjointly  with  several 
other  theaters  in  the  neighborhood.  Each  gets  a  share  of  the  people 
who  seek  entertainment  in  the  evenings  in  that  portion  of  the  city, 
but  one  of  them,  it  will  be  assumed,  gets  less  than  the  others,  while 
its  cost  of  operation  is  about  the  same.  It  is  only  a  matter  of  time 
until  the  familiar  sign  "This  Place  Has  Changed  Hands"  will  be 
seen,  the  place  is  closed  for  a  week  to  emphasize  the  change  of 
ownership  and  to  advertise  the  new  opening,  a  few  changes  are 
made  in  the  theater,  and  business  is  begun  again.  From  this  time 
on,  it  gets  its  full  share  of  the  neighborhood's  theater  traffic,  or  even 
more. 

What  is  the  change?  The  only  fundamental  change  is  the 
manager.  The  new  manager  has  brought  with  him  either  a  knowl- 
edge of  the  motion-picture  theater  business,  or  an  ability  to  learn 
the  business  while  nmning  his  theater.     The  new  manager  under- 

Cop'jrigfil,  1011,  by  American  School  of  Correspondence. 


165 


2  THE  MOTION  PICTURE 

stands  from  experience  or  study,  or  is  able  to  learn  and  understand, 
not  only  his  theater  itself,  but  the  people,  his  people,  his  patrons  who 
come  to  his  theater.  They  are  his  people,  for  he  makes  them  his. 
He  studies  them,  learns  them,  pleases  them,  and  gets  their  money. 

Several  instances  of  change  of  o^\Tiership  have  been  studied 
especially  for  the  purpose  of  setting  forth  the  obsers^ations  in  this 
book  in  order  that  theater  managers  might  profit  by  them. 

Change  of  Management  (1).  There  were  three  theaters  in  the 
same  city  block,  with  no  other  theaters  within  three  city  blocks  in 
either  direction.  The  difference  in  traffic  among  the  theaters  in 
the  block  was  easily  noticeable  to  a  motion-picture  scout  who  gave 
the  following  two  reasons  why  one  of  the  theaters  got  less  business 
than  its  proper  share.  First,  it  was  the  oldest  of  the  three  and  had 
the  least  attractive  front,  each  of  the  later  houses  having  been  de- 
signed to  surpass  the  older  house  in  outside  attractiveness.  Second, 
it  was  at  the  distant  end  of  the  block  from  a  busy  cross-street,  so  that 
the  larger  number  of  people  coming  to  that  block  reached  the  other 
two  theaters  first,  and  could  reach  the  oldest  theater  only  by  passing 
the  other  two. 

When  the  place  "changed  hands" — an  event  which  came  to 
pass  just  after  the  midwinter  holidays — the  only  new  element  in  the 
theater  was  the  new  manager.  The  place  was  not  even  closed  for 
spectacular  effect  of  an  "opening  night."  The  new  manager,  how- 
ever, was  noticed  at  once.  He  took  upon  himself  the  duties  of  usher 
in  his  theater,  and  made  it  a  point  to  stand  at  the  exit  door  as  the 
patrons  who  had  seen  the  show  came  out.  If  a  patron  chanced  to 
glance  at  liim,  the  glance  was  met  with  a  smile  and  a  remark,  "Call 
again,"  or  "Good  night,"  or  "Did  you  Hke  the  show?"  or,  apologetic- 
ally, "We  are  not  so  crowded  except  on  Saturday  nights."  He  was 
studying  his  people  as  they  came  out  of  the  theater;  he  learned  them, 
and  they  learned  to  know  him  and  came  to  expect  him  to  be  there. 
Many  of  them  learned  to  express  praise  of  a  good  program  which 
had  pleased  them  particularly,  while  others  by  such  questions  as 
"\Mien  are  you  going  to  have  another  Biography"  or  a  compHment 
upon  any  specific  film  picture,  told  him  just  what  pictures  were  pleas- 
ing his  people.  He  began  to  put  out  signs  of  "Good  Selig  Tonight" 
and  "Repeated  by  Request,"  from  time  to  time,  and  gained  for  his 
theater  its  just  share  of  the  business  of  the  block. 


166 


MOTION-PICTURE  THEATER  3 

Under  one  manager,  this  theater  failed;  under  another  manager 
the  same  theater,  unchanged  except  as  to  manager,  succeeded. 
The  pay  roll  was  the  same,  the  quality  of  film  about  the  same,  the 
projection  about  the  same;- but  the  manager  tried  to  learn  what  films 
would  please  his  people,  then  obtained  that  class  of  subject  and  from 
popular  factories,  and  advertised  in  front  of  his  theater  in  the  par- 
ticular manner  which  he  found  best  to  attract  his  passers-by. 

Change  of  Management  (£).  Of  three  theaters  in  two  adjacent 
blocks  in  a  city,  one  had  a  front  of  really  artistic  design  in  mission 
style,  finished  in  the  dark  stain  familiar  in  mission  furniture.  This 
place  "changed  hands"  during  the  summer.  The  new  manager 
painted  that  mission  finish  a  pure  white,  just  like  the  other  two 
theaters,  his  competitors.  A  handsome  wall  sign  at  the  entrance, 
containing  the  announcement  of  the  films,  and  decorated  with  minia- 
ture electric  lights,  completed  the  only  changes  noticeable  as  im- 
provements. The  "Happy  Hour"  always  had  had  as  good  a  program 
as  its  competitors  in  the  next  block,  but  from  this  time  on  it  had 
also  just  as  good  a  patronage  as  they. 

Change  of  Management  (3).  A  small  "store  front"  theater  in 
a  large  city  was  located  on  a  cross-street  near  the  principal  retail 
business  street  of  the  city.  The  owner  and  manager  lost  money  all 
through  his  lease  of  a  year  and  at  the  end  of  the  year  was  glad  to  sell 
his  fittings  at  a  sacrifice  to  relieve  himself  of  the  burden  of  removing 
them  to  vacate  the  building  for  the  owner.  The  purchaser  was 
an  experienced  motion-picture  theater  man,  nmning  two  theaters 
on  other  streets  in  the  same  city.  He  studied  the  location  (before 
purchasing)  and  saw  that  the  situation  was  peculiar. 

Because  the  theater  was  located  on  a  side  street,  the  crowds 
of  shoppers  did  not  pass  its  door.  Just  around  the  corner,  on  the 
main  business  street  for  shoppers,  were  two  other  picture  theaters, 
taking  the  trade  of  the  shoppers  and  leaving  the  side  street  theater 
almost  deserted.  The  experienced  theater  man  saw  that  this  theater 
location  did  not  have  an  equal  chance  to  obtain  the  patronage  of  the 
shoppers,  but  he  conceived  the  idea  that  there  must  exist  a  class  of 
people  other  than  empty-headed  shoppers  strolling  into  the  first  open 
theater  door,  and  he  decided  to  buy  the  place,  thoroughly  renovate 
it,  put  in  a  sloping  floor,  and  make  an  appeal  to  a  special  class  of 
patrons  by  offering  a  special  class  of  program. 


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4  THE  MOTION  PICTURE 

The  old  show  had  been  running  a  program  of  two  reels  of  film, 
a  new  reel  and  a  holdover  each  day;  one  song  illustrated  with  lantern 
slides  and  changed  twice  a  week,  the  singer  being  the  pianist;  and 
one  vaudeville  act.  This  program  was  given  for  five  cents.  The 
new  manager  reduced  the  size  of  the  picture  screen,  thereby  giving 
a  brighter  picture  and  reducing  the  jiggle  of  the  picture  while  still 
using  the  same  projecting  machine.  Then  the  vaudeville  act  was 
eliminated  and  a  really  good  singer  was  employed.  The  picture 
films  were  changed  to  a  program  of  "daily  change"  of  the  two  reels 
without  holdover — for  this  manager  hoped  to  build  up  some  patron- 
age with  office  and  store  people  who  would  come  every  day,  either 
noon  or  evening.  To  this  end,  his  song  was  changed  every  day.  This 
gave  him  a  complete  change,  both  pictures  and  song,  every  day, 
with  a  short  program  of  only  about  forty  to  forty-five  minutes,  but 
with  the  quality  at  the  very  top,  particularly  in  the  matter  of  the 
music. 

The  result  was  unqualified  success,  and  profit.  The  difference 
lay  in  the  training  of  the  manager.  The  first  manager  did  not  under- 
stand his  environment  thoroughly,  and  tried  to  run  a  do\\Tito\STi 
theater  for  shoppers  on  a  street  where  there  were  no  shoppers;  the 
new  manager  recognized  this  limitation  of  location  and  did  not  strive 
to  fight  against  it,  but  instead  reasoned  that  there  must  exist  in  that 
section  a  clientele  de  luxe,  a  class  of  busy  people  with  an  inclination 
for  good  music,  and  who  would  come  every  day  for  a  short  program  of 
high  quality.  His  success  with  the  theater  formerly  a  failure  has 
proved  his  wisdom. 

Change  of  Management  (4).  This  theater  was  one  of  two, 
about  a  block  apart,  on  a  business  street  through  a  residence  dis- 
trict of  a  city.  It  was  run  by  a  man  who  owned  the  store  building 
and  who,  lacking  a  tenant,  thought  'it  only  necessary  to  put  in  a 
theater  front  and  a  picture  screen  and  hire  an  operator  and  a  film 
service.  He  did  not  make  his  rental  value.  A  young  man  living  in 
the  neighborhood  and  working  downtown  flu  ring  the  dav  offered 
to  take  the  management  of  the  theater,  which  was  open  evenings 
only.  This  young  man  had  no  experience  whatever  as  manager, 
but  studied  the  traffic  of  the  neighboring  picture  show  close  enough 
to  see  that  the  only  difference  between  the  two  shows  was  the  quality 
of  the  films  and  projection.    He  took  the  management  of  the  house, 


168 


MOTION-PICTURE  THEATER  5 

changed  his  fihn  service,  hired  a  good  projection  operator — thereby 
increasing  the  running  expenses— put  out  a  "changed  hands"  sign 
to  induce  the  people  to  make  a  trial  visit,  advertised  a  special 
program  with  hand-bills  every  week,  and  got  his  share  of  the  trade 
from  the  first  week. 

In  this  case,  the  first  manager  made  a  failure  because  he  did 
not  study  his  own  theater  to  find  out  what  was  the  matter  with  it. 
The  second  manager  made  a  success,  because  he  studied  the  two 
theaters  comparatively  to  learn  wherein  the  one  which  he  thought  of 
taking  was  inferior  to  the  competitor,  knowing  that  it  was  necessary 
only  to  equal  his  competitor  to  obtain  his  half  of  the  traffic,  and 
knowing — from  a  head  count  and  an  expense  sheet — that  half  the 
traffic  in  his  theater  would  pay  him  a  profit. 

Change  of  Management  (5).  This  case  was  pure  economy  in 
pay  roll.  One  man  started  a  store-front  theater  and  quit  before 
the  end  of  the  first  winter.  The  second  winter,  another  man  started 
in  the  same  store,  ran  it  for  two  winters,  and  continues  to  operate  it. 
This  picture  show  is  isolated,  being  in  a  small  town,  the  only  show 
in  the  town.  The  man  who  ran  this  show  for  the  first  winter  knew 
notliing  of  the  motion-picture  business.  He  furnished  a  store  room 
with  screen  and  chairs,  a  piano  and  a  projection  machine,  hired  a 
pianist,  an  operator,  and  a  film  service,  and  started  the  show,  act- 
ing himself  as  doorkeeper.  The  show  ran  evenings  only,  and  paid 
no  profit.  The  owner  concluded  that  the  town  was  too  small  to 
support  a  motion-picture  theater,  and  closed  the  house. 

The  second  manager,  who  ran  the  theater  the  second  year, 
was  a  projection  operator.  He  did  not  take  in  any  more  nickels 
than  the  first  manager,  but  he  paid  less  money  to  his  pianist,  he  got 
his  film  ser\dce  at  a  lower  figure  because  he  knew  what  he  could 
afford  and  did  not  pay  more  than  it  was  worth,  and,  being  the  pro- 
jection operator  himself,  he  did  not  have  that  expense  to  deduct 
from  the  receipts  before  calculating  his  own  personal  profits  from 
the  show  business.  The  net  profits  to  him  were  such  as  enabled 
him  to  nm  the  show  year  after  year,  and  to  prove  that  the  to\vn  would 
support  a  motion-picture  theater  when  the  theater  was  run  by  a 
manager  who  understood  the  limitations  of  his  field  and  governed 
his  program  and  his  expense  sheet  accordingly. 

Art  of  the  Manager.    These  illustrations  of  theaters  which  have 


169 


6  THE  MOTION  PICTURE 

failed  under  one  manager  and  then  have  succeeded  under  another, 
every  one  with  only  some  small  difFerence  in  paint,  or  program,  or 
pay  roll,  are  given  to  illustrate  the  statement  that  in  many  if  not 
nearlv  all  cases  the  eleinent  of  success  or  failure  lies  with  the  manager. 

Every  one  of  the  instances  show  merely  that  the  new  manager 
adapted  his  theater  to  the  conditions  wliich  he  found  existing  as 
limitations  upon  the  theater  when  he  took  charge  of  it. 

In  the  example  (1),  the  new  manager  decided  to  make  his 
theater  different  from  his  competitors  by  learning  the  particular 
things  which  would  please  his  people  and  by  giving  them  a  personal 
courteous  attention.     He  won  success. 

In  the  example  (2),  the  new  manager  decided  that  his  theater 
was  as  good  as  his  competitor's  except  that  it  had  a  sober  front, 
almost  repellent  to  the  joy  seeker.  He  changed  the  color  of  the 
front,  and  won  success  by  eliminating  his  theater's  handicap. 

In  the  example  (3),  the  new  manager  decided  that  an  ordinary 
theater  could  not  be  run  successfully  in  that  location,  so  he  tried  an 
extraordinary  program,  and  won  success. 

In  the  example  (4),  the  new  manager  decided  that  his  theater 
had  only  one  handicap  over  his  competitor,  the  quality  of  films 
and  projection.    He  removed  this  fault,  and  won  success. 

In  the  example  (5),  the  new  manager  saw  that  the  expense  could 
be  reduced  even  though  the  receipts  could  not  be  increased,  and  his 
profit  lay  in  the  difference.  Notice  that  he  did  not  give  a  poorer 
program,  but  gave  the  same  quantity  and  quality  program  at  a  smaller 
expense. 

In  (2)  and  (4),  the  new  manager  found  a  single  feature  in  which 
his  theater  was  behind  his  competitors;  he  brought  that  feature  up 
to  his  competitors  and  won  his  share  of  the  business. 

In  (1),  in  (3),  and  in  (5),  the  location  of  the  theater  was  not 
good,  but  each  of  the  managers  found  a  different  solution;  in  (5),  it 
was  simple  economy;  in  (1),  it  was  personal  attention  to  the  likes 
and  dislikes  of  his  patrons;  in  (3),  it  was  a  Napoleonic  stroke  of 
generalship. 

Reviving  a  "Sick"  Picture  Theater.  There  is  only  one  symptom 
which  attracts  attention  to  the  disease  of  the  theater,  and  that  is  the 
lack  of  satisfactory  net  profit.  This  symptom  may  be  due  to  either 
of  two  diseases .-/r.^/,  that  the  income  is  not  large  enough;  and  second. 


170 


SCENE  FROM  PHOTOPLAY,   "THE  LAST  APPEAL" 
Courtesy  of  Independent  Moving  Pictures  Co.,   Xeic  York 


MOTION-PICTURE  THEATER  7 

that  the  expense  is  too  large.  In  example  (5),  the  new  manager  did 
not  think  the  income  could  be  increased,  but  he  reduced  the  expense. 
In  examples  (1),  (2),  and  (3),  the  new  manager  did  not  decrease  the 
expense,  but  by  his  skill  he  increased  the  income.  In  example  (4),  the 
new  manager  found  both  income  and  expense  too  low,  and  increased 
both,  increasing  the  income  more  than  the  expense. 

The  "sick"  picture  theater  must  be  studied  particularly  with 
reference  to  its  competition  and  its  location.  Then  the  traffic  of  the 
community  must  be  studied  to  learn  whether  there  is  sufficient  traffic 
to  support  the  theater.  The  question  of  traffic  may  be  studied  in 
two  phases:  first,  whether  there  is  enough  to  support  the  "sick" 
theater  if  it  were  to  get  its  proportion  of  the  total;  and  second,  whether 
it  is  necessary  or  advisable  to  try  to  surpass  competition  and  secure 
for  the  "sick"  theater  more  than  its  proportion.  The  second  propo- 
sition is  a  case  for  a  doctor  of  experience. 

Competition.  Study  every  point  of  difference  which  can  be  found 
between  the  theater  in  question  and  its  competitor  or  competitors: 
The  color  of  the  front;  the  decorations  of  the  front;  the  announcement 
signs  for  number,  attractiveness,  and  general  desirability;  the  poster 
service  used  for  the  films;  the  style  of  ticket  window;  the  courtesy 
of  the  cashier;  the  method  of  taking  the  tickets  at  the  door  and  the 
courtesy  of  the  doorkeeper;  the  seat  arrangement;  the  width  of  aisles 
and  the  confusion  or  convenience  of  incoming  and  outgoing  patrons 
when  the  place  is  handling  a  crowd;  the  comfort  of  the  seats,  their 
style,  their  width,  and  the  space  between  the  rows,  whether  cramped 
or  liberal  to  permit  passing  an  occupied  seat;  the  number  of  seats; 
the  decoration  of  the  walls;  the  illumination  during  the  pictures  and 
during  the  intermissions;  the  quality  of  the  films,  w^hether  new  or 
old  and  whether  clean  or  dirty  or  scratchy;  the  quality  of  the  pro- 
jection, whether  dim  or  brilHant,  whether  steady  in  light  or  full  of 
flicker,  whether  steady  in  position  or  full  of  jumps  and  jiggles  on 
the  screen,  and  whether  the  whole  picture  on  the  screen  rises  and 
falls  with  a  wave-like  motion;  the  quality  of  the  song  slides  and  their 
projection;  the  quality  of  the  singer;  the  music  or  entertainment 
during  intermissions  in  the  program ;  the  character  of  the  vaudeville, 
and  whether  it  suits  the  audience  or  displeases  them,  being  endured 
only  for  the  remainder  of  the  program;  the  frequency  of  change  of 
program,  pictures,  songs,  and  vaudeville. 


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8  THE  MOTION  PICTURE 

^^^len  a  point  of  difference  is  found,  study  it  to  see  whether 
the  difference  is  to  the  advantage  of  the  theater  under  study  or  whether 
it  is  to  the  advantage  of  the  competitor.  Then  decide  whether  any 
change  should  be  made  in  the  theater  studied. 

The  result  of  tliis  study  should  determine  whether  it  is  possible 
at  a  reasonable  expense  to  bring  the  theater  studied  up  to  equaUty 
with  its  neighbors,  and  the  study  should  permit  the  making  of  an 
expense  sheet  for  running  the  theater  in  equahty  wath  its  neighbors. 
The  new  expense  sheet  may  be  smaller  or  larger  than  the  old;  that 
is  immaterial,  for  the  question  is:  "What  will  be  the  expense  of 
making  this  theater  equal  to  its  neighbors  or  competitors  that  it  may 
divide   the   trade  with  them?" 

Traffic.  An  actual  "head  count"  of  the  patronage  of  the  neighbor- 
ing or  competing  theaters  must  be  made,  and  a  count  of  the  number 
of  people  "held  out"  during  the  heavier  hours  of  traffic,  if  such  occurs. 
Add  the  total  of  all  admissions  for  the  theater  studied  and  its  com- 
petitors, and  divide  by  the  number  of  theaters  for  the  hours  of  lighter 
traffic  and  divide  by  the  number  of  seats  in  the  capacity  of  the  houses 
for  the  hours  of  heavier  traffic  when  patrons  are  being  held 'out  at 
the  door.  This  will  give  the  revenue  to  be  expected  in  the  theater 
studied  if  it  were  brought  up  to  quaUty  with  its  competitors. 

Income  vs.  Expense.  The  two  amounts  thus  obtained — the 
income  from  the  ticket  w^indow  and  the  expense  account  for 
equaling  competition — will  give  the  profit  of  the  theater  without 
consideration  for  side  lines  of  profit. 

The  ticket-window  profit  may  be  increased  by  a  judicious  use  of 
side  lines  for  profit,  unless  the  matter  of  such  devices  has  been  abused 
and  thus  brought  into  disrepute  in  the  neighborhood. 

The  side  lines  which  may  be  considered  are:  (-/)  paid  adver- 
tising on  a  drop  curtain,  displayed  during  intermissions;  (2)  paid 
advertising  sUdes  for  the  stereopticon ;  (5)  paid  advertising  space 
on  printed  programs  handed  to  the  patrons  either  on  entering  or 
leaving  the  theater;  (4)  paid  advertising  on  hand-bills  containing 
theater  announcements  and  distributed  through  the  neighborhood; 
(5)  sales  of  candy  in  the  theater  during  the  intermissions ;  (6)  control 
or  co-operation  of  a  confectionery  and  refreshment  business  adjacent 
to  the  theater;  (7)  automatic  slot  vending  machines. 

Managing  a  Theater  for  Profit.    Continuous  study  of  the  theater, 


172 


MOTION-PICTURE  THEATER  9 

day  by  day  and  week  by  week,  comparing  it  with  its  competitors 
and  comparing  it  with  other  theaters  at  a  distance  but  similarly 
located,  similarly  surrounded,  and  similarly  equipped,  will  enable 
the  manager  to  determine  just  what  his  theater  ought  to  do  in  the 
way  of  gross  receipts,  expense,  and  net  profits.  This  gives  him  a 
theoretical  result  which  should  be  attained  by  his  account  books. 
If  his  books  do  not  show  the  amount  of  profit,  and  from  the  different 
sources,  which  his  study  shows,  he  should  study  his  theater  as  a 
"sick  theater"  and  strive  to  learn  why  he  is  not  doing  as  well  as  his 
competitors,  or  as  well  as  some  other  theater  operated  by  another 
manager  under  comparatively  the  same  conditions.  A  study  of 
other  theaters,  near  and  far,  a  study  of  the  technical  papers,  and  a 
study  of  the  advertising  and  educational  matter  constantly  sent  out 
by  manufacturers  in  the  motion-picture  industry,  films,  machines, 
accessories,  and  sundries,  will  give  the  manager  a  correct  idea  of 
what  his  theater  should  accomplish.  Then  he  may  study  his  own 
house  to  learn  whether  it  accomplishes  what  it  should,  and  if  not, 
he  may  learn  by  still  further  study  what  is  lacking  that  prevents  it 
from  attaining  daily  its  just  deserts  and  its  maximum  profits. 

STARTING  A  THEATER 

The  first  detail  is  to  choose  a  location,  then  to  decide  how  ex- 
tensive an  investment  the  location  will  justify  because  of  its  prospective 
patronage.  After  that,  the  building  and  operating  of  the  theater 
becomes  routine  detail,  the  theater  succeeding  or  failing  according 
to  the  ability  of  the  manager,  his  attention  to  the  details  of  the  theater 
and  its  patronage,  and  his  ability  to  learn  and  understand  the  salient 
facts  in  his  studies. 

Selecting  a  Location.  Among  Competitors.  In  this  case,  the 
proposed  location  may  be  studied  as  though  the  site  were  already 
occupied  with  a  "sick  theater."  The  traffic  upon  the  existing  theaters 
may  be  tallied  up  and  expressed  in  dollars  per  week;  then  a  reason- 
able increase  may  be  figured,  for  a  new  theater  added  to  the  ones 
already  existing  will  increase  the  total  of  the  traffic.  This  total  may 
be  divided  to  learn  how  much  money  will  be  taken  at  the  ticket 
window  of  the  proposed  new  house.  Side  lines  for  profit  then  are 
studied  and  added,  the  total  income  and  the  total  expense  are  ob- 


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10  THE  MOTION  PICTURE 

tained  and  compared,  and  the  answer  is  obtained  to  the  question: 
How  much  will  another  theater  in  this  locality  pay  in  profits? 

This  study  may  be  made  upon  the  basis  of  another  small  store- 
front theater  competing  with  one  or  two  already  established,  or  it 
may  be  made  upon  the  basis  of  constructing  a  larger  theater.  If 
a  larger  theater  is  to  be  compared  with  a  store-front  competitor,  the 
total  traflBc  may  be  increased  largely,  say  doubled,  for  the  larger, 
more  pretentious  house  will  draw  traffic  over  a  larger  area,  for  a 
greater  distance  both  ways  on  the  street,  and  then  in  turn  will  take 
a  larger  share  as  its  proportion  of  the  total,  particularly  in  view  of 
larger  seating  capacity  on  the  rush  evenings  when  all  houses  are 
holding  the  patrons  out  for  want  of  seating  capacity. 

Neiv  Territory.  The  only  difference  is  that  the  traffic  to  be  ex- 
pected is  more  indefinite  in  calculation.  It  may  be  predicted  very 
closely  by  a  "head  count"  of  the  people  passing  a  possible  location. 
The  count  should  be  made  every  evening  for  a  week,  or  during  all 
such  hours  of  the  week  as  the  theater  would  be  open  for  business. 
In  the  absence  of  other  data,  this  number  may  be  divided  by  ten  to 
obtain  the  number  of  nickels  which  may  be  expected,  or  one-half 
cent  for  each  person  passing  the  possible  theater.  Towns  vary  in 
this  respect.  To  obtain  the  proper  figure  for  the  town  in  which  the 
possible  theater  is  being  studied,  go  to  other  theaters  in  the  town, 
count  for  a  few  evenings  the  number  of  people  passing  the  theater 
and  the  number  of  people  passing  into  the  theater,  and  learn  whether 
the  theater  gets  one  out  of  eight,  or  one  out  of  twelve,  or  one  out  of 
twenty  who  pass  the  door.  To  the  casual  mind,  the  following  law 
may  seem  without  reason,  but  it  will  hold  true:  The  proportio7i  of 
people  who  pass  into  an  ordinary  picture  theater  to  the  people  who 
pass  by  will  be  about  the  same  in  all  parts  of  the  same  city,  and  the 
patronage  of  a  theater  in  open  territory  may  be  predicted  from  a  count 
of  passers  at  the  site  where  it  is  proposed  to  start  the  theater. 

Having  thus  by  "head  count"  obtained  a  figure  for  the  ticket 
window  receipts,  the  expenditure  for  establishing  the  theater,  and 
the  pay  roll  for  operating  it  may  be  determined  in  advance,  and  a 
theater  may  be  built  in  that  location  which  will  pay  a  reasonable 
profit  on  its  investment  and  running  expenses — in  short,  a  success- 
ful theater  may  be  established,  because  it  will  be  established  in  har- 
mony with  the  possibilities  of  its  location  and  environment. 


174 


MOTION-PICTURE  THEATER  11 

A  person  looking  for  a  theater  location  will  find  many  "possible" 
places  where  he  might  rent  or  build  and  start  his  theater.  All  of 
these,  or  at  least  several  of  the  more  promising  of  them,  should  be 
studied  carefully  and  in  detail,  making  up  an  income  and  expense 
acco\mt  for  each  of  the  locations;  then  the  best  may  be  selected  and 
the  theater  started. 

Small  Town.  This  is  a  case  for  study,  not  so  much  to  determine 
the  place  in  the  town  where  the  theater  should  be  located,  but  to 
determine  whether  the  town  itself  is  a  suitable  location  for  a  theater, 
whether  it  will  support  a  theater  and  how  much  of  an  investment 
and  pay  roll  will  be  justified. 

The  "head  count"  for  a  town  so  small  that  only  one  theater  is 
possible  may  be  taken  from  the  census  reports.  Any  town  of  1,000 
people  will  support  a  motion-picture  theater  if  it  is  nm  by  the  right 
man  and  in  the  right  way.  It  is  found  that  a  "one  theater"  town 
will  pay  weekly  at  the  ticket  window  from  two  and  one-half  to  five 
cents  per  capita  on  its  census  population.  A  town  of  1,000  people 
will  yield  from  $25  to  $50  per  week  on  a  show  running  six  nights  per 
week  and  Saturday  afternoon  or  whatever  day  of  the  week  the  coun- 
try people  use  for  market  day,  usually  Saturday,  but  not  always. 

The  gross  revenue  of  the  small  town  being  determined  by  mul- 
tiplying the  census  population  by  a  reasonable  amount  to  be  ex- 
pected, say  three  and  one-half  or  four  cents  per  week,  it  remains  for 
the  prospective  theater  manager  and  owner  to  decide  whether  he 
can  bring  his  expense  sheet  sufficiently  below  the  gross  receipts  to 
leave  an  acceptable  profit  for  his  time  and  whether  with  such  an 
expense  sheet  he  can  give  an  acceptable  show  which  will  continue  to 
bring  the  money  after  the  first  few  weeks,  when  the  novelty  of  the 
theater  has  worn  away. 

The  manager  must  make  himself  thoroughly  familiar  with  any 
city  ordinances  regulating  the  operation  of  motion-picture  theaters. 
Even  small  towns  are  having  such  laws  enacted. 

Financing.  For  the  man  who  believes  that  he  can  make  money 
in  managing  a  picture  theater,  whether  he  has  experience  in  the 
picture  theater  business  or  not,  yet  who  has  not  the  necessary  funds 
for  starting  it,  there  occurs  the  problem  of  securing  the  money,  and 
upon  such  terms  as  will  yield  him  a  profit  and  not  pass  all  the  profits  to 
the  capitalist  who  furnishes  the  money  and  does  no  work. 


175 


12  THE  MOTION  PICTURE 

For  a  small  enterprise,  which  will  not  require  more  than,  say 
S2,000,  with  anticipated  profits  (excluding  manager)  of  S50  to  $75 
per  week,  the  manager  and  promoter  may  profitably  arrange  to 
"spUt  the  profits"  with  the  capitalist.  This  will  yield  the  manager 
a  revenue  of  S25  to  §37.50  per  week  if  he  can  nm  the  theater  accord- 
ing to  his  expectations,  while  the  capitalist,  who  is  sole  owner  of  the 
theater  under  the  agreernent,  will  receive  a  liberal  return  on  his  in- 
vestment, even  allowing  for  depreciation  of  the  theater  fittings. 

For  a  larger  enterprise  involving  much  more  capital  the  capitahst 
may  insist  upon  an  unequal  division  of  profits,  because  the  anticipated 
salarv'  for  the  manager  and  promoter  would  look  large.  In  such  an 
instance,  the  manager  should  insist  upon  a  fixed  salary  for  himself 
carried  as  a  part  of  the  expense  pay  roll  of  the  theater;  and  in  addi- 
tion an  unequal  dix-ision  of  the  net  profits,  giving  the  capitalist  the 
greater  portion. 

For  any  enterprise  where  more  than  one  man  puts  up  any  money, 
a  form  of  stock  company  or  partnership  agreement  should  be  drawn 
up  and  signed  by  all.  This  cannot  be  much  more  than  informal 
unless  placed  in  the  hands  of  an  attomey-at-law  for  proper  form, 
but  in  any  event  it  should  be  a  signed  agreement.  In  such  a  financing 
plan,  the  manager  operating  the  theater  will  receive  a  salary  as  a 
theater  expense,  and  all  profits  will  be  di^•ided  by  the  partners  or 
stockholders  in  proportion  to  the  amounts  of  money  each  of  them 
furnished.  A  share  of  the  net  profits  is  provided  for  the  manager 
and  promoter  by  giving  him  a  share  in  the  ownership  which  he  earns 
by  his  work  in  organizing  the  company  instead  of  by  papng  cash. 
This  may  be  one-tenth  to  one-half  stock  interest  or  ownership. 

A  Store=Front  City  Theater  Building.  A  vacant  business  house 
having  been  selected  both  for  location  and  for  size,  the  process  of  con- 
verting it  into  a  motion-picture  theater  is  to  remove  the  glass  front  and 
framing  for  the  door  and  window,  to  replace  it  with  a  closed  front 
a  few  feet  back  from  the  sidewalk  fine  into  which  are  built  the  ticket 
seller's  booth  and  the  entrance  and  exit  doors  and  on  the  inside  of 
which  is  built  the  projection  operator's  booth.  At  the  inner  end  of 
the  room  a  muslin  screen  about  3  by  4  yards  is  stretched.  The  room 
is  filled  with  rows  of  chairs,  either  kitchen  chairs  or  opera  chairs,  as 
the  expense  justified  by  the  location  will  permit,  and  a  piano  is  placed 
near  the  picture  screen. 


176 


MOTION-PICTURE  THEATER 


13 


Floor  Plan.  A  few  general  rules  which  may  be  followed  in  floor- 
plan  construction  are  given  herewith;  aside  from  these  a  large  varia- 
tion in  floor  plan  is  possible. 

The  projecting  machine  should  be  at  one  end  of  the  room  and 
the  picture  screen  at  the  other  end,  both  being  so  high  above  the  floor 
that  the  rays  of  light  from  the  projecting  machine  to  the  lower  edge  of 
the  screen  will  not  be  interrupted  by  patrons  passing  dowm  the  aisle. 

The  front  of  the  room  must  be  closed  against  the  lights  of  the  street, 
even  when  a  patron  is  entering. 

The  operator's  room  mv^t  be  laid  out  with  reference  to  comfort 
and  convenience,  6  feet  square  is  a  desirable  smaller  limit. 

The  floor  space,  if  limited,  must  be  laid  oid  to  seat  as  many  people 
05  possible,  up  to  the  number  which  the  traffic  study  will  require. 


1- 

:=  I  I  I  :  :  1 1  ^ 

i ? 

:iii:i::iz   !x> 

1      ^     1        lUJ  LJ  LjJ  ID  LJ  a_J  UJ  LU 

lL'^--I 

r-r/       _ 

e-  _^ ._.___.__ 

^  o        —    —    ^     —     —    —     —    — 

_    _     ^     —     —    —     —    — 

^^^^^^^^ 

—   e'-o'— 

—  J'-O'-^ -#''0'               — 

—I —  6-0'  i 

Fig.  1.     Floor  Plan  for  a  Small  Store  -Front  Theater 

The  operator's  booth  must  be  lined  with  sheet  iron,  top,  bottom, 
and  sides,  with  a  door  having  a  latch,  and  with  two  look-out  holes, 
one  for  the  beam  of  light  from  the  lenses  and  another  at  least  a  foot 
square  and  with  the  center  at  the  height  of  the  operator's  eye,  through 
which  the  operator  may  look  to  see  his  picture  on  the  screen;  these 
requirements  are  for  protection  against  flrc. 

A  floor  plan  which  is  adaptable  to  the  general  requirements  of 
any  store-front  theater  is  given  in  Fig.  1.  This  shows  an  arrangement 
for  the  maximum  seating  capacity  for  a  store  room  22  feet  by  b^  feet  in- 
side the  walls.  The  seating  capacity  shown  is  192.  The  front  partition 
of  the  theater  is  placed  6  feet  back  from  the  sidewalk.  The  ticket 
booth  extends  forward  from  this  partition.  A  still  deeper  front  is 
desirable  if  the  floor  space  can  be  spared;  it  gives  advertising  space; 


177 


14  THE  MOTION  PICTURE 

it  gives  opportunity  for  decorative  efforts  without  the  expense  of 
decorating  the  entire  front  of  the  business  house;  it  suggests  retire- 
ment in  the  theater,  and  when  the  prospective  patron  steps  off  the 
sidewalk  he  feels  that  he  is  already  within  the  theater,  even  before 
he  has  purchased  his  admission  ticket. 

The  entrance  and  exit  doors  in  the  partition  should  be  double 
doors.  The  entrance  doors  at  A  should  swing  both  ways,  while  the 
exit  doors  at  B  should  swing  outward  but  not  inward. 

The  ticket  booth  in  Fig.  1  is  6  feet  by  5  feet  inside,  with  a  shelf 
1  foot  wide  across  the  front  for  making  change.  The  three  glass 
windows  should  be  made  with  removable  sash  in  order  that  screen 
wire  or  grille  mav  be  substituted  in  the  warm  weather. 

The  operating  booth  occupying  the  upper  part  of  the  space  D 
is  built  over  the  ticket  booth  upon  an  elevated  platform  about  5 
by  9  feet  in  size.  As  the  patrons  of  the  theater  are  required  to  pass 
under  this  platform  it  should  be  built  upon  a  platform  about  7  feet 
from  the  floor.  A  stanchion  is  set  from  floor  to  ceiling  at  E,  about 
9  feet  from  the  side  wall  and  5  feet  from  the  partition,  and  with  this 
stanchion  as  a  corner  post  a  platform  is  built  to  cover  the  space  D, 
then  closed  in  with  walls  from  the  platform  to  the  ceiling  to  form  the 
operating  room.  ^Yindows  for  projection  and  lookout  are  left  in  the 
wall  toward  the  screen  J,  and  another  window  may  be  left  in  the 
end  for  ventilation  and  over  the  doors  A  in  the  partition.  Entrance 
to  the  operating  room  is  obtained  by  means  of  the  ladder  at  F,  which 
extends  upward  along  the  wall  and  through  a  hole  about  30  inches 
square  in  the  floor  of  the  operating  room. 

Below  the  operating-room  platform,  extending  from  the  stanchion 
E  to  the  wall,  a  screen  G  should  be  placed  to  prevent  the  light  of  the 
street  from  reaching  the  screen  when  the  doors  A  are  open;  this 
may  be  a  curtain  hung  from  the  edge  of  the  operator's  booth.  The 
doorkeeper  stands  at  the  post  marked  H.  A  movable  chain  or  bar 
is  provided  to  extend  from  the  stanchion  E  to  the  wall  of  the  ticket 
booth  to  close  the  passage  at  the  dotted  line  I.  This  enables  the 
doorkeeper  to  hold  back  patrons  who  come  so  near  the  close  of  a 
picture  or  act  that  they  would  be  interfered  with  by  patrons  passing 
out,  or  by  patrons  for  whom  there  is  no  seat.- 

The  piano  may  be  at  K,  either  automatic  or  manual.  The  screen 
J  is  shown  at  one  side  of  the  center;  this  has  two  advantages  in  the 


178 


MOTION-PICTURE  THEATER  15 

floor  plan  as  shown.  It  gives  more  room  for  the  piano  and  singer  at 
the  side  of  the  screen,  and  it  brings  the  center  of  the  screen  nearer 
to  the  direct  line  from  the  projection  machine  at  the  end  I  of  the 
operating  room  at  D. 

Another  method  of  building  an  operating  room  is  to  build  it 
over  the  cashier's  booth,  extending  through  the  partition  and  pro- 
jecting into  the  theater  room  as  far  as  the  stanchion  E.  Set  two 
stanchions  like  E  and  build  the  platform  to  the  ceiling,  placing  the 
ladder  F  beside  the  short  wall  of  the  cashier  ticket  seller's  booth, 
just  inside  the  entrance  door.  The  projecting  machine  will  stand 
against  the  wall  of  the  operating  room  at  the  exit-door  side,  and  the 
projection  and  look-out  windows  should  be  placed  in  the  front  wall 
accordingly. 

A  space  of  6  or  8  feet  between  the  front  chairs  and  the  picture 
screen  should  be  allowed,  as  the  pictures  cannot  be  viewed  at  a  very 
close  range.  If  the  seats  marked  X  are  left  out,  the  added  con- 
venience to  patrons  in  passing  out  of  the  theater  may  more  than 
compensate  for  the  decreased  seating  capacity. 

Lighting  Methods.  Ceiling  lights,  say  a  sixteen-candle-power 
lamp  for  each  50  square  feet  of  floor,  should  burn  during  the  inter- 
missions. Shaded  wall  lamps,  say  an  eight-candle-power  lamp 
every  10  or  12  feet  along  each  wall,  should  burn  all  the  time,  includ- 
ing the  time  during  the  pictures.  The  wall  lamps  should  be  so 
shaded  that  the  light  will  not  shine  upon  the  picture  screen  nor 
upon  the  eyes  of  the  audience. 

The  term  "daylight-theater"  is  used  to  designate  a  theater  in 
which  the  auditorium  lights  are  not  turned  off  during  the  projection 
of  the  pictures.  This  result  is  attained  by  hanging  the  ceiling  lamps 
in  sixty-degree  conical  shades,  or  the  equivalent  in  ornamental  shades, 
so  that  the  light  from  each  ceiling  lamp  covers  a  circle  on  the  floor 
under  the  lamp  but  does  not  shine  on  the  picture  screen,  nor  does 
it  shine  back  toward  the  entrance  into  the  eyes  of  the  seated  patrons. 
The  lamps  thus  shaded  must  be  distributed  over  the  theater  ceiling, 
and  not  grouped,  as  then  the  desired  eft'ect  would  be  lost. 

Low-Cost  Store  Front.  To  build  for  the  lowest  cost  of  starting 
operation,  in  a  location  where  only  the  minimum  expense  is  justified 
or  where  only  the  minimum  expense  is  desired,  the  front  partition 
may  be  modeled  upon  the  style  shown  in  Fig.  2.    This  is  all  simple 


179 


16 


THE  MOTION  PICTURE 


carpenter  work  and  painter  work.  The  complete  change  in  the  store 
room,  ready  for  chairs,  piano,  wiring  and  projecting  machine,  should 
not  exceed  S150;  200  chairs  of  the  kitchen  variety  at  $100;  electric 
lamps  and  \^aring  at  $100;  a  projecting  machine  at  $165;  and  a  rented 
piano — the  total  expense  amounting  to  about  $500.  With  a  small 
additional  amount  for  supplies  and  initial  advertising  expense,  the 
manager  will  be  able  to  open  his  doors  to  the  pubhc  at  a  total  cash 
expense  of  not  more  than  $600,  and  no  debts. 

Only  country  towns  of  small  size  without  competition,  or  un- 


rig. 2.    A  Simple  Front  Design  for  a  Store-Front  Theater 

occupied  or  non-competitive  city  territory,  will  permit  a  successful 
theater  with  so  simple  an  estabUshment. 

Such  a  theater  could  be  established  upon  a  prospective  ticket 
sale  of  $110  to  $150  per  week,  since  the  return  for  the  manager's 
labor  and  a  return  for  the  cash  invested  must  be  earned  in  addition 
to  the  expense  sheet  given  below.  The  item  of  "Supplies"  includes 
tickets,  carbons,  condensers,  lamp  renewals,  machine  repair  parts 
etc.,  and  piano  tuning,  including  in  this  case  also  the  rent  of  the  piano. 
This  is  a  fair  expense  account  for  a  small  city  house,  even  though  at 


180 


MOTION-PICTURE  THEATER  17 

a  much  larger  initial  cost,  where  competition  does  not  compel  a  larger 
expense,  yet  where  the  patrons  constantly  are  comparing  this  residence 
district  theater  with  the  more  pretentious  down-town  motion-picture 
theaters.  With  such  distant  competition  for  comparison,  it  is  neces- 
sary to  maintain  a  quality  of  picture  projection  and  music  which 
will  stand  the  comparison,  if  the  theater  is  to  be  a  continued  business 
with   profits. 

The  cost  of  operating  this  theater,  evenings  only — for  it  would 
be  either  in  a  small  town  or  in  a  residence  territory  of  a  city — for  a 
program  of  two  reels  of  film  and  a  song,  would  be,  by  the  week,  about 

as    follows : 

% 

Rent  and  heat $  10 .  00 

Electricity 5.00 

Film 20.00 

Song  Slides 2 .00 

Supplies 13.00 

Operator 15.00 

Cashier 3.00 

Doorkeeper 5.00 

Pianist 5.00 

Singer • 5.00 

Weekly  Expense $  83.00 

In  a  non-competitive  small  city,  not  only  will  the  rent  be  lower, 
but  the  wage  rate  will  be  lower  throughout. 

Elaborate  Store-Front.  The  floor  plan  will  be  the  same  in  this 
case  as  in  Fig.  1,  the  difference  being  found  in  the  quality  and  appear- 
ance of  the  elements  going  to  make  up  the  theater. 

A  decorative  front  such  as  is  illustrated  in  Fig.  3  will  cost  $500 
to  $2,000  for  the  front  partition  complete  with  operating  room  and 
cashier's  booth,  including  all  the  decoration  in  front  of  the  partition. 
Another  $500  or  more  will  be  needed  to  raise  the  floor  and  to  install 
200  opera  chairs  at  $1.20  to  $1.60  each.  The  inside  decorations  and 
the  picture  screen  of  modern  type  will  raise  the  expense  $200  to  $300 
at  least.  The  total  expense  need  not  exceed  $6,000;  with  any  pre- 
tensions toward  beauty  and  luxury,  it  cannot  be  kept  below  $2,000. 

For  designing  and  building  the  front,  a  firm  in  the  special  work 
should  be  employed,  unless  the  manager  who  is  starting  the  theater 
is  of  long  experience  and  knows  exactly  what  he  wants.  The  large 
number  of  such  theaters  which  have  been  built  has  developed  con- 


181 


18 


THE  :^IOTIOX  PICTURE 


struction  firms  and  workmen  particularly  skilled  in  such  work,  whose 
very  presence  on  the  job  will  insure  that  refinement  and  perfection 
of  detail  which  the  manager  desires  but  which  the  inexperienced 


Fig.  3.    A  Decorative  Front  Design  for  Store-Front  Theater. 

manager  employing  inexperienced  workmen  is  Hkely  to  overlook, 
leaving  his  house  inferior  to  those  of  his  competitors. 

In  selecting  or  approving  a  plan  by  a  professional  designer,  the 
manager  should  see  that  the  cashier's  booth  is  large  enough  for  com- 
fort all  the  year  round  and  that  the  projection  operator's  booth  is  large 


182 


MOTION-PICTURE  THEATER  19 

enough  for  two  operators  and  two  projecting  machines.  Not  only  may 
competition  enforce  the  employment  of  two  operators,  but  it  will 
be  found  positive  economy  to  give  the  operator  an  assistant  during 
the  rush  hours  of  Saturday  night. 

In  a  house  of  this  class,  a  manager's  control  panel  and  signal 
system  should  be  installed  at  the  door  where  the  ticket-taker  stands, 
that  he  may  signal  the  operator  to  begin  projection,  and  may  ring 
for  the  singer,  etc.,  controlling  the  conduct  of  the  program  par- 
ticularly during  the  rush  hours  when  the  passing  of  numbers  cf 
people  in  or  out  may  delay  the  beginning  of  the  next  picture. 

The  program  selected — by  this  term  "program"  is  included 
the  cjuality  as  well  as  quantity  of  pictures,  song,  music,  and  vaude- 
ville— must  follow  the  custom  of  the  city  in  which  the  theater  is 
located,  if  the  certainty  of  a  proper  division  of  patronage  is  desired. 
A  departure  from  the  custom  of  the  city  may  result  in  a  larger  suc- 
cess, or  may  result  in  failure.  Such  a  departure  was  made  in  the 
theater  discussed  in  "Change  of  Management  (3),"  and  serves  as 
an   example. 

A  specimen  expense  sheet  of  a  high-class  store-front  picture 
theater  is  here  given. 

WEEKLY    EXPENSE    SHEET 

Rent,  of  complete  theater,  week $  40.00 

Film  rent,  three  reels  daily  change..  .  50.00 

Carbons 1 .  00 

Pianist 15.00 

Violinist 10.00 

Drummer 12 .00 

Usher 2.50 

Electricity 18 .00 

Song  Slides 2.00 

Cashier 5.00 

Singer 18.00 

License 4 .  00 

Projection  operator 18 .00 

Porter 4.00 

Ticket  taker 5.00 

General  Expense 10 .00 

Total  weekly  expense,  not  including 

manager $214 .  50 

Receipts,  average,  six  nights  $240,  Sunday  $100;  total  weekly  receipts, 
average. 


183 


20  THE  MOTION  PICTURE 

Specimen  Expense  Sheet  of  a  High-Closfi  Store-Front  Picture  Theater. 
The  figures  given  above  are  the  actual  expense  sheet  of  a  house  of  this  class 
in  a  residence  district  of  Chicago.  The  rent  item  is  the  amount  paid  per  week, 
making  a  rental  of  $173  per  month  or  $2,080  per  year,  but  this  is  for  the  house 
equipped  with  chairs  and  projecting  machine,  so  that  the  expense  sheet  is 
carrying  the  item  of  depreciation  of  investment  as  a  part  of  the  rent  item. 
The  cost  of  opening  this  house  for  business  was  in  the  neighborhood  of  $3,000. 

This  particular  theater  charges  a  five-cent  admission  seven  days  in  the 
week.  The  seating  capacity  is  300.  A  one-hour  program  is  given  at  7,  8,  9, 
and  10  P.M.  on  week  days  and  at  2,  3,  4,  5,  6,  7,  8,  9,  10  p.m.  on  Sundays — 
thirty-three  shows  per  week,  three  reels  and  a  song  in  each  program.  The 
film  is  one  reel  third-run,  one  reel  not  more  than  ten  days  old,  and  one  reel 
not  more  than  three  months  old,  daily  change,  for  which  $50  per  week  is  paid. 
Two  different  songs  are  given,  alternating  in  every  other  program,  with  one 
singer.  Music  is  furnished  by  an  orchestra  of  three.  The  item  of  "Sundry 
Expense"  includes  tickets,  coal,  condensers,  poster  service,  machine  repairs, 
lamp  renewals,  piano  tuning,  etc. 

In  this  theater,  the  manager  takes  profits  rather  than  a  salary.  He  has 
no  capital  invested,  but  in  the  $40  per  week  rent  he  is  paying  a  return  to  the 
capitalist  for  the  investment. 

Slo'ping  Floor.  This  method  of  floor  construction  raises  the 
eyes  of  patrons  in  the  back  seats  above  the  heads  in  the  front  rows, 
givino-  the  patrons  at  the  back  of  the  house  a  better  view  of  the  pic- 
ture screen  or  stage.  The  sloping-floor  construction  is  necessary 
in  houses  classing  above  the  simplest  of  store-front  theaters.  It  is 
a  good  bid  for  business  to  equal  or  excel  a  competitor,  because  it 
gives  a  greater  comfort  to  the  patron,  and  makes  the  picture  theater 
resemble  more  closely  the  larger,  more  pretentious  city  houses. 

A  side  view  of  a  store-front  theater  with  one  wall  removed  is 
shown  in  Fig.  4.  This  shows  the  sloping  floor,  and  one  method  of 
constructing  it  for  store-front  houses.  AMiere  the  building  is  erected 
specially  for  theater  purposes,  even  though  it  be  a  part  of  a  business 
block  and  a  store-front  in  appearance,  this  plan  is  easily  followed, 
but  where  an  old  building  is  remodeled  it  is  necessary  to  cut  the  floor 
joists  at  the  picture  screen  end  if  the  entrance  doors  are  to  be  level 
with  the  street  or  sidewalk. 

A  raised  floor  may  be  constructed  upon  the  store-room  floor  by 
building  a  few  low  trestles  or  "horses"  across  the  house,  say  18 
inches  or  2  feet  high  at  the  street  partition  of  the  house,  and  getting 
lower  toward  the  picture  screen.  Joists  for  the  inclined  floor  are 
laid  sloping  upon  these  trestles,  and  taper  to  a  point  at  the  toe  where 
the  new  sloping  floor  meets  the  old  level  floor.    .The  slope  may  extend 


184 


MOTION-PICTURE  THEATER 


21 


two-thirds  the  way  to  the  picture  screen,  and  the  front  third  of  the 
house  may  be  level. 

Steps  may  be  built  between  the  street  level  and  the  raised  floor, 
or  the  floor  may  be  sloped  up  from  the  street  line  to  avoid  steps, 
even  carrying  a  slope  into  the  aisle  of  the  theater. 

The  floor  plan  arrangement  for  the  street  end  of  the  theater 
of  Fig.  1  is  suitable  for  the  theater  of  Fig.  4,  or  the  projection  booth 
may  be  built  over  the  ticket  booth. 

In  the  theater  of  Fig.  4,  the  requirement  for  the  height  of  the 
projection  room  floor  and  for  the  height  of  the  projection  window 
is  that  the  rays  of  light  from  the  lens  to  the  lower  edge  of  the  picture 
screen  should  clear  the  heads  of  persons  standing  in  the  aisle. 

A  comfortable  amount  of  slope  for  the  theater  floor  is  1  foot  in 
8.    This  is  the  slope  shown  in  Fig.  4. 

Seats  upon  a  sloping  floor  must  be  the  "theater  seat,''  as  shown 
in  end  view  in  Fig.  4;  or  if  chairs  the  legs  must  be  sawed  to  make 


Fig.  4.   Theater  with  Sloping  Floor 

the  chair  comfortable.  \\Tien  theater  seats  are  bought,  it  should  be 
specified  that  they  are  for  use  upon  a  sloping  floor,  and  they  will 
be  furnished  accordingly  by  the  manufacturer.  The  seats  between 
the  bottom  of  the  slope  and  the  picture  screen  are  ordered  for  level 
floor. 

Stage.  If  a  stage  is  to  be  built,  either  for  vaudeville  purposes, 
or  for  scenic  effect  in  the  theater,  the  stage  floor  should  be  3  feet 
above  the  theater  floor  in  front  of  the  stage.  The  proscenium  arch 
in  such  a  stage  may  extend  to  within  1  foot  of  a  low  ceiling,  and 
within  3  feet  of  each  side  wall. 


185 


22  THE  MOTION  PICTURE 

If  for  decorative  effect  only,  the  picture  screen  may  be  stretched 
permanently  across  the  opening.  The  projected  picture  should  be 
kept  a  foot  or  two  above  the  bottom  of  the  screen. 

If  for  use  for  vaudeville,  the  stage  should  be  10  or  12  feet  deep, 
with  two  wings  on  each  side.  An  interior  flat  should  be  at  the  back 
and  a  street  scene  half-way  between  the  back  flat  and  the  drop  curtain. 
The  picture  screen  should  be  at  the  front,  just  behind  the  drop  cur- 
tain. By  "interior  flat"  is  meant  a  flat  painted  scene  showing  the 
interior  of  a  room.  There  may  be  two  pairs  of  wings  for  the  interior 
scene  setting  and  one  pair  of  wings  for  the  street  scene,  with  flies 
sufficient  to  conceal  the  ceiling  from  the  patrons  in  the  front  row  of 
chairs. 

If  the  stage  is  used  for  vaude^^lle,  footlights  must  be  installed, 
with  switch  at  the  ticket-taker's  station  at  the  entrance,  and  the 
projection  operator  must  be  provided  with  a  mask  for  his  stereopticon 
which  will  cover  the  stage  opening  but  not  the  sides  of  the  arch. 

Picture  Screen.  For  a  screen  against  a  wall,  the  wall  may  be 
painted  white,  or  given  a  "white  finish"  coat,  such  as  plasterers  use 
in  finishing  a  wall  smooth.  Over  this  white  surface,  stretch  a  sheet 
of  thin  muslin,  with  as  few  seams  as  possible.  Have  the  seams  run 
horizontally,  and  tack  the  musUn  all  around  the  edges.  A  neat  and 
inexpensive  finish  is  obtained  by  nailing  to  the  wall  a  frame  of  wide 
picture-molding,  mitering  the  corners  as  though  the  screen  were 
framed  and  hung  upon  the  wall. 

Any  wall  screen  or  drop  curtain  screen  may  be  treated  by  a  coat 
of  paint  containing  finely  divided  particles  of  some  glittering  sub- 
stance, such  as  finely-divided  aluminum  dust,  or  finely-powdered 
glass,  or  the  curtain  may  be  painted  with  any  sticky  paint  and  the 
metallic  dust  or  powdered  glass  thrown  or  blown  upon  it  and,  when 
the  sticky  paint  dries,  a  glittering  surface  will  remain  upon  the  screen 
producing  what  is  known  as  the  metal-surfaced  screen.  These  tricks 
of  producing  metal  surfaces  are  well  known  by  sign  painters. 

The  picture  projected  upon  such  a  metallic-surfaced  screen  is 
more  brilliant  in  its  light  portions,  while  retaining  all  the  detail  of 
its  darker  or  shadowy  portions.  At  the  same  time,  the  dead  white 
screen  may  be  a  matter  of  personal  preference,  or  where  all  com- 
petitors use  a  metallic  surface,  the  dead  white  of  thin  cloth  backed 
by  white  plaster  cleaned  from  dust  occasionally  to  keep  it  white, 


186 


MOTION-PICTURE  THEATER  23 

and  kept  free  from  stains  at  all  times,  together  with  a  smaller  and 
brighter  picture,  may  be  urged  as  an  advertising  point  of  advantage 
over  the  methods  of  competitors. 

The  mirror  screen  increases  the  brilliancy  of  a  picture.  Also, 
it  is  Hkely  to  give  "haloes"  or  radiant  bright  spots  to  some  places  of 
the  auditorium  if  the  surfacing  is  not  sufficiently  dense.  The  cost 
runs  to  $300  or  $400. 

The  theoretical  mirror  screen  as  announced  to  the  public 
consists  of  a  sheet  of  plate  glass,  the  size  of  the  projected  picture; 
this  glass  is  silvered  upon  the  back  and  ground  to  a  smooth  ground- 
glass  finish  upon  the  front  surface.  The  ground-glass  surface  gives 
a  good  screen  surface  for  projection,  even  if  not  backed,  being  equiva- 
lent to  a  surface  of  finely-powdered  glass,  but  all  light  which  passes 
through  the  ground-glass  surface  is  reflected  by  the  mirror  back  to 
the  surface  again  and  through  it  to  the  spectators  in  the  theater. 
The  result  is  a  large  increase  in  brilliancy  in  the  picture  projected 
with  the  same  conditions  of  lamp  and  lenses. 

^lirror  screens  are  made  also  by  painting  the  surface  of  a  large 
mirror  with  a  frosting  surface,  such  as  a  thin  mixture  of  English 
"whiting"  with  water  and  a  little  glue.  A  substitute  for  the  real 
mirror  screen  is  a  mirror  over  which  is  stretched  a  sheet  of  tliin 
muslin.  The  muslin  should  be  seamless — muslin  sheeting  8  feet 
wide  may  be  obtained  in  the  market — or  the  seams  must  be  made 
by  setting  the  two  selvedged  edges  against  each  other  and  whipping 
them  together  with  a  very  fine  stitch  without  lapping  the  fabric. 
\Miere  a  lap  seam  is  used,  the  mirror  beliind  the  fabric  shows  the 
seam  so  very  plainly  that  it  becomes  decidedly  objectionable. 

The  thin  fabric  screen  backed  by  a  mirror  is  an  improvement 
upon  the  fabric  screen  backed  by  a  white  wall.  The  cheapness  of 
such  an  arrangement  is  based  on  the  fact  that  the  mirror  used  to 
back  such  a  fabric  screen  may  be  made  economically  of  small  sheets 
of  silvered  glass  rather  than  of  a  single  large  sheet,  the  small  sheets 
being  set  snugly  together  without  bevel  edges  and  without  mounting, 
that  the  lines  of  joining  may  not  be  noticed  by  the  patrons.  Small 
clamps  may  hold  the  mirrors  to  a  supporting  wall  or  vertical  plat- 
form, care  being  taken  to  make  the  entire  mirror  surface  fiat. 

AMiere,  because  of  clearing  the  stage  for  vaudeville  acts,  it  is 
necessary  to  roll  the  picture  screen,  the  screen  must  be  made  of 


187 


24  THE  MOTION  PICTURE 

opaque  white  fabric,  and  fitted  with  a  heavy  roller  to  stretch  it  when 
rolled  down,  or  tackle  must  be  used  at  the  bottom  to  stretch  it.  A 
waving  curtain  produces  a  very  objectionable  effect  in  the  picture. 
Metallic  surfaces  have  been  used  on  roller  'picture  screem.  Great 
care  must  be  used  to  avoid  wrinkles  when  the  metallic  surface  is 
used,  for  the  small  wrinkles  are  much  emphasized  by  the  reflecting 
nature  of  the  sparkling  surface. 

Special  Buildings.  A  theater  building  having  a  50-foot  front 
and  seating  five  hundred  or  more  people  may  be  built  at  a  cost  aside 
from  the  lot  of  S10,000  to  .$20,000,  according  to  design  and  location. 
Such  houses  usually  are  run  to  a  longer  program  than  an  hour  of 
pictures,  being  vaudeville  houses  rather  than  simple  picture  houses. 

The  principles  of  operating  such  a  house  do  not  vary  from  those 
of  the  smaller  picture  theaters.  The  same  tact,  skill,  and  ability  to 
learn  from  experience  and  from  observation  of  other  houses  of  the 
class  are  required  of  the  manager.  The  same  balancing  of  gross 
income  against  expense,  and  the  same  possibilities  of  side  lines  for 
additional  profits,  exist. 

A  house  of  this  size  in  the  residence  districts  usually  runs  a  vaude- 
ville program  and  charges  an  admission  of  ten  cents  or  more. 

Example  of  Special  Theater  Building.  The  class  of  theater  occupy- 
ing a  specially  constructed  building,  in  the  residence  districts  of  Chicago,  is 
well  represented  by  the  particular  theater  from  which  the  following  facts  are 
taken : 

The  lot,  50  by  125  feet,  upon  which  the  building  is  erected,  was  estimated 
in  value  at  $10,000;  and  the  erection  of  the  building  and  its  equipment  ready 
for  the  public,  cost  $15,000,  making  a  total  expense  in  the  building  itself  of 
$25,000.  For  this  investment  the  owner  takes  a  rental  of  $5,200  per  year  from 
the  receipts  of  the  theater.  This  item  is  considered  an  item  of  rent  in  the  theater 
expense  sheet,  and  is  paid  weekly  at  the  rate  of  $100  per  week,  as  rent. 

The  program  consists  of  four  acts  of  vaudeville,  two  reels  of  film,  and  a 
song.  There  is  an  orchestra  of  four  pieces.  The  program  lasts  about  an  hour 
and  a  half  to  an  hour  and  three-quarters.  The  program  is  given  twice  each 
night,  once  on  Wednesday  afternoon,  once  on  Satm-day  afternoon,  and  twice 
on  Sunday  afternoon;  eighteen  performances  per  week,  of  which  four  are  on 
Sunday.     In  case  of  a  long  vaudeville  program,  the  song  is  omitted. 

The  house  contains  800  seats,  of  which  600  are  on  the  main  floor  and 
200  on  the  balcony.  Of  these,  350  seats  are  sold  at  twenty  cents  and  450  at 
ten  cents;  the  total  value  of  a  full  house  is  $115.  An  average  evening  in  fair 
weather  is  a  house  and  a  half  for  the  two  performances.  Of  the  twenty-cent 
seats,  fifty  are  the  front  rows  of  the  balcony;  this  raises  the  tone  of  the  balcony 
as  a  seat  location  and  helps  to  sell  the  house  out  when  nearly  full. 

The  film  service  is  one  reel  ten  days  old  and  one  reel  not  more  than  three 


188 


MOTION-PICTURE  THEATER  25 

months  old,  change  twice  a  week;  for  this  service,  the  price  paid  is  $20  per 
week.  The  entire  program,  vaudeville  and  film  and  song,  is  changed  twice 
each    week. 

The  illustrated  song  slides,  when  used,  and  the  singer  as  well,  are  fur- 
nished free  by  the  music  publishers  for  the  advertising  value. 

WEEKLY    EXPENSE   OP  A   SMALL   VAUDEVILLE  THEATER 

Rent,  per  week $100 .00 

Film  service,  per  week 20 .00 

Carbons 1 .00 

Orchestra  of  four  pieces,  per  week ....  91 .00 

Two  ushers '. 5 .  00 

One  fire  guard 7 .00 

One  stage  manager 20 .  00 

One  stage  helper 7 .00 

Electricity,  per  week 30  .00 

Cashier 7.00 

License 4 .  00 

Poster  title  ser\ace 5 .  00 

Projection  operator 18.00 

Vaudeville,  average  weekly 500.00 

Porter  and  watchman 12  .00 

Ticket  taker 8.00 

Sundry  small  expenses,  average  per 

week 25.00 

Weekly  expense  sheet $860  .00 

Average  receipts  for  six  days,  fourteen  performances,  $900.00;  for 
Sunday,  four  performances,  $315.     Average  weekly  receipts,  $1,215. 

Large  Exclusive  Picture  House.  Only  in  the  shopping  district 
of  a  city  can  a  sufficient  number  of  patrons  be  found  to  fill  a  large 
house  repeatedly  for  short  programs.  The  data  given  here  for  such 
a  theater  is  taken  from  a  theater  on  the  busiest  retail  business  street 
of  one  of  the  largest  cities  of  the  United  States,  a  theater  representative 
of  the  highest  class  of  motion-picture  theater. 

The  house  is  open  fourteen  hours  per  day,  seven  days  each 
week,  from  9  a.  m.  until  11  p.  m.  The  program  is  three  reels 
of  film  (or  three  pictures,  not  necessarily  each  a  full  reel)  and  two 
illustrated  songs.  The  film  is  all  first  run,  changing  the  three  reels 
three  times  each  week,  without  holdovers,  but  a  good  film  picture 
frequently  v/ill  be  repeated  a  few  weeks  later,  with  the  advertising 
sign,  "Repeated  by  request."    The  songs  are  changed  weekly.    Two 


189 


26  THE  MOTION  PICTURE 

singers  are  employed  for  the  two  songs  of  each  program,  one  male 
voice  and  one  female  voice. 

Three  projection  operators,  working  at  the  same  time  in  the 
operating  room,  put  on  the  program.  Two  of  these  operators  have 
motion-picture  projecting  machines,  while  the  third  operator  pro- 
jects notliing  but  stereopticon  slides,  both  announcement  slides  and 
song  slides,  attending  also  to  the  illumination  of  the  auditorium  dur- 
ing the  intermission. 

The  order  of  the  program  is  as  follows:  The  show  starts  with 
a  few  announcement  slides;  then  the  first  motion-picture  operator 
puts  on  the  first  film  picture.  As  the  end  of  the  film  picture  approaches 
the  stereopticon  operator  stands  ready  and  projects  the  song  title 
upon  the  tailpiece  of  the  film,  the  pianist  opens  the  introduction  to 
the  song  as  the  title  appears  and  the  song  follows  without  a  second 
of  lost  time.  At  the  close  of  the  song,  the  second  motion-picture 
operator  stands  ready  and  begins  projection  at  a  signal  from  the 
stereopticon  operator,  the  last  slide  of  the  song  dissolving  into  the 
title  of  the  next  film  picture.  In  the  same  manner  the  screen  con- 
tinues without  interruption  of  projection  into  the  second  song  and 
then  into  the  third  film  picture  by  the  first  projection  operator.  At 
the  close  of  the  third  film  picture  the  lights  are  turned  on,  the  crowd 
is  allowed  a  few  minutes  for  passing  out  and  in,  the  candy  man 
makes  a  trip,  and  the  program  is  repeated.  The  house  is  "dark ' 
about  fifty  minutes  for  the  program  of  three  pictures  and  two  songs, 
and  is  "light"  for  about  five  minutes  for  the  intermission. 

For  the  ordinary  day,  fifteen  performances  are  given  in  the 
fourteen  hours.  On  Saturday,  the  busy  day,  an  extra  performance 
is  given,  making  sixteen  in  all. 

The  house,  equipped  fully  for  the  operation  of  the  theater, 
represents  an  invested  capital  of  $100,000.  The  building  was  com- 
pletely remodeled  for  the  theater,  under  lease  to  the  theater  mana- 
gers. It  is  not  owned  by  the  theater  managers,  and  a  rental  of  $48,000 
per  year  is  paid.  This  includes  heating.  Figured  upon  a  weekly 
basis  for  the  weekly  expense  sheet,  this  rental  is  $923  per  week. 

The  theater  seats  seven  hundred  people.  The  admission  price 
is  ten  cents,  anywhere  in  the  house,  giving  a  value  for  a  "full  house" 
of  $70. 

The  attendance  averages  about  six-tenths  of  the  total  capacity 


190 


IMOTION-PICTURE  THEATER  27 

— six-tenths  of  seven  hundred  seats,  filled  fifteen  times  on  an  average 
for  six  days,  6,300  tickets  per  day  for  six  days  and  400  more  on 
Saturday  for  the  extra  performance,  about  44,500  tickets  per  week, 
or  $4,450  weekly  receipts  at  the  ticket  window.  On  many  Saturdays 
— the  busy  day  with  sixteen  performances — the  ticket  sale  reaches 
nearly  10,000,  or  $1,000. 

The  theater  is  operated  by  two  sets  of  employes,  called  the 
day  force  and  the  night  force,  each  working  seven  hours  continuously. 
The  day  force  works  from  9  a.m.  until  4  p.m.,  the  night  force 
then  coming  on  and  working  until  1 1  P.  m.  Thirty-five  employes 
are  on  the  pay  roll  of  the  theater  itself,  aside  from  the  manager 
and  his  clerical  help. 

The  orchestra  comprises  pianist  and  drummer,  and  a  "sound 
effect"  man  for  adding  something  of  realism  to  the  pictures  by  supply- 
ing some  of  the  sounds  attendant  in  nature  upon  the  scene  represented. 

Weekly  Expense.  The  item  of  rent  is  a  matter  fixed  by  contract  with 
the  owTier  of  the  building.  It  appears  high  when  compared  with  rental  values 
of  theaters  of  similar  seating  capacity  but  located  in  the  residence  districts 
of  the  city  w^here  the  land  values  are  not  so  high. 

In  the  item  of  electric  current,  it  must  be  noted  that  this  theater  runs 
fourteen  hours  per  day,  against  an  average  of  five  hours  per  day  for  a  residence 
district  theater.  The  electric  lighting  and  electric  signs  in  front  of  the  theater 
are  profuse,  and  most  of  the  lamps  burn  the  full  fourteen  hours  per  day  that 
the  theater  is  open. 

The  film  rental  item  of  SI 26  per  week  for  three  reels  changed  three  times 
a  week  takes  into  account  the  large  nimiber  of  times  that  each  reel  is  run 
through  the  projecting  machine.  The  wear  upon  the  film  naturally  is  greater 
for  the  fifteen  shows  per  day  which  this  theater  gives  than  it  would  be  in  a 
residence  district  show  of  four  performances  daily.  It  is  true  further  that 
"first  run"  film  is  the  most  e.xpensive  run  of  film  for  the  theater  manager 
to  buy,  and  that  all  of  this  theater's  film  is  first  run  film. 

The  item  of  "sundry  expenses"  includes  tickets,  carbons,  lamp  renewals, 
machine  repairs  and  depreciation,  piano  tuning,  painting  a  large  sign  three 
times  per  week  with  each  change  of  program,  and  many  minor  expenses. 

In  each  of  the  items  where  the  pay  roll  is  involved,  it  is  remembered 
that  the  item  is  doubled  to  provide  for  the  two  forces  of  employes  covered 
by  the  list,  the  day  force  and  the  night  force. 

Six  projection  operators  are  employed,  three  for  the  day  force  and  three 
for  the  night  force;  of  each  set  of  three,  are  two  motion  operators  and  one  slide 
operator. 

A  guard  in  full  police  uniform  is  in  attendance  at  the  entrance  door.  A  fire 
guard  is  required  by  the  rules  of  the  fire  department  of  the  city. 

The  orchestra  of  six  employes  comprises  the  two  pianists,  the  two  drum- 
mers, and  the  two  sound  artists. 


191 


28  THE  MOTION  PICTURE 

Of  the  fovir  singers,  each  is  required  to  sing  seven  or  eight  times — a 
day's  work.  Two  are  on  the  day  force  and  two  on  the  night  force;  each  sings 
once  in  each  show. 

WEEKLY   EXPENSE  SHEET 

Rent  and  heat,  per  week $923 .00 

•    Electricity,  per  week 200 .00 

Film  rental 126.00 

Song  slides 2.00 

Sundry  expenses,  per  week 130.00 

License 8.00 

6  Projection  operators 112.00 

2  Cashiers 30.00 

2  Uniformed  police  at  door 36 .  00 

2  Fire  guards 28 .00 

2  Ticket  takers 30 .00 

6  Orchestra  and  soimd  effects 210.00 

4  Singers 100.00 

3  Porters 36.00 

8  Ushers 80.00 

Manager,  per  week 40 .  00 

Assistant  manager,  per  week 25.00 

Stenographer  and  bookkeeper 15.00 

Messenger  boy 6 .  00 

Telephone 2,00 

Office  supplies  and  sundry 6.00 

Average  weekly  expenses $2,145.00 

Average  weekly  receipts,   $4,450. 

Country   Theater  (1).     The  theater  from  which   this  expense 

sheet  was  taken  was  unsuccessful.     The  expense  seems  about  a 

minimum  for  a  theater  in  which  the  manager  must  employ  help  for 

all  of  his  ser\^ice,  yet  the  gross  receipts  of  the  theater  did  not  justify 

even  this  expense. 

WEEKLY    EXPENSE   SHEET 

Rent $  3.50 

Film  service,  7  reels  weekly 18.00 

Express  charges 1 .00 

Electricity 3.00 

Operator 10  .00 

Ticket  seller 1 .  50 

Pianist 3 .  00 

Coal  (winter  expense) 2 .00 

Tickets,  carbons  and  sundry 1 .00 

Total  weekly  expense $43.00 


192 


MOTION-PICTURE  THEATER  29 

Average  weekly  receipts,  $40. 

This  town  had  a  census  population  of  1,100  people,  giving  a  probable 
weekly  ticket  window  income  of  $27.50  to  $55. 

Country  Theater  (2).  In  the  same  town,  under  a  different 
manager.  The  experience  of  the  first  theater  had  showii  about  what 
gross  income  could  be  expected.  The  expense  account  was  planned 
to  fall  below  the  anticipated  income  by  enough  to  leave  a  profit  for 
the  manager. 

WEEKLY  EXPENSE  SHEET 

Rent $  3.50 

Film,  eight  reels,  express  paid 12.00 

Electricity 3  .  00 

Operator 

Ticket  seller 1 .00 

Pianist 2  .  50 

Coal  (winter  expense) 2 .00 

Tickets,  carbons  and  sundry 1  .00 

Newspaper  advertisements .50 

Total  weekly  expense $25.50 

Average  weekly  receipts,   $45. 

The  commercial  run  of  film  satisfied  his  audience  for  quality, 
and  age  of  subject  was  immaterial,  as  all  were  new  to  his  patrons. 
The  eight  reels  were  run  as  follows:  Two  on  ^Monday  night,  one 
new  and  one  holdover  on  Tuesday  night;  one  new  and  one  holdover 
Wednesday  night;  one  new  and  one  holdover  Thursday  night;  one 
new  and  one  holdover  Friday  night;  two  new  reels  and  one  holdover 
Saturday  afternoon  and  Saturday  evening.  This  gave  a  three-reel 
show  on  Saturday  and  prices  of  ten  cents  for  adults  and  five  cents 
for  children  were  charged. 

The  manager  ran  the  projecting  machine  himself,  thus  avoiding 
an  expenditure  for  an  operator's  salary. 

The  ticket  seller  sold  tickets  and  noted  that  the  patrons  dropped 
them  into  a  ticket  box  at  the  door,  which  box  could  be  seen  by  the 
manager  from  time  to  time  as  he  chanced  to  look. 

The  pianist  seems  the  only  luxury  on  the  bill  of  expense.  The 
small  advertisement  in  the  local  newspaper  seems  good  business 
judgment. 

Country  Theater  (3).     In  the  same  town,  during  the  summer. 


193 


30  THE  MOTION  PICTURE 

During  this  season,  the  patronage  of  the  country  folk  is  largely  with- 
drawn except  on  Saturdays.  The  operation  of  the  picture  theater  was 
changed  to  suit  the  changed  conditions  for  the  summer  months. 

The  theater  building  or  room  was  held  over  the  summer  at  the 
uniform  rental  rate  for  the  following  winter's  business.  The  film 
service  was  reduced  to  three  reels  for  the  Saturday  show,  and  shows 
were  given  only  on  Saturday  afternoon  and  evening.  Admission 
was  five  and  ten  cents,  as  on  Saturdays  during  the  winter. 

WEEKLY   EXPENSE    SHEET 

Rent $  .3.50 

Film,  three  reels  express  paid 5.00 

Electricity 1.00 

Ticket  seller .25 

Pianist .75 

Sundry  expense .50 

Newspaper  advertisements 1 .00 

Total  weekly  expense $12 .00 

Receipts  averaged  between  $15  and  $20  weekly.  In  addition  to 
the  profit  of  the  one  day  at  the  theater,  the  manager  had  other  employment 
during  the  week. 

Country  Theater  (4).  This  theater  is  located  in  a  country  town 
whose  census  population  is  but  six  hundred  people.  The  gross 
income  which  might  be  expected  in  such  a  town,  according  to  the 
rule,  would  be  S15  to  $30  per  week,  and  this  is  based  upon  a  show 
running  six  nights  and  one  afternoon  per  week. 

WEEKLY   EXPENSE  SHEET 

Rent,  heat  and  ticket  seller,  two  days $     3 .00 

Film,  five  reels,  two  days 4 .  50 

Express  charges .35 

Expense  for  acetylene-lamp  supplies .30 

Sundry  expenses 1 .00 

Total  weekly  expense $     9.15 

Average   weekly   receipts,    $14. 

For  an  exhibition  room,  a  lodge  hall  seating  about  one  hundred  and 
twenty-five  people  was  obtained  at  a  price  of  two  nights  for  $3,  including 
the  heating,  and  a  ticket  s-eller  was  furnished  as  a  favor. 

The  item  of  film,  five  reels  for  $4.50,  was  attained  by  "splitting  the 
week"  with  another  theater  in  a  neighboring  town,  which  used  the  five  reels 
during  the  remainder  of  the  week. 


194 


MOTION-PICTURE  THEATER 


31 


The  total  expense  of  starting  this  theater  was  about  $60  for  a  complete 
projecting  outfit  with  acetylene  lamp.  Aside  from  this  there  was  no  expense 
but  the  curtain  for  the  picture  screen.  The  manager  and  operator  was  regularly 
employed  during  the  day,  his  show  profits,  being  "velvet." 

The  program  given  was  three  reels  the  first  night  and  two  new  reels  and 
a  selected  holdover  reel  for  the  second  night.    The  price  was  five  cents. 

Airdome.  This  name  has  been  adopted  to  define  a  motion- 
picture  theater  in  the  open  air.  A  fenced  enclosure  is  chosen,  or 
a  canvas  8  to  10  feet  high  is  erected  upon  stakes  to  form  an  enclosed 
yard.  At  one  end  a  projection  house  or  even  a  projection  platform 
is  built;  at  the  other  end,  a  picture  screen  of  usual  theater  size  is 
erected.  Chairs  are  arranged  before  the  screen  as  in  any  motion- 
picture  theater,  and  the  entire  conduct  of  the  airdome  is  quite  the 
same.     A  platform  may  be  built  before  the  screen  for  vaudeville. 

The  airdome  is  for  fair  weather  only.  The  novel  idea  seems  to 
please  the  general  public,  whether  the  airdome  is  operated  in  a  coun- 
try to^vn  or  upon  a  vacant  lot  in  a  large  city. 

The  illustration,  Fig.   5,  shows  an  airdome    upon    a  city  lot 


Fig.  5.   The  Airdome 

beside  a  business  house.  The  lot  is  divided  by  the  picture  screen 
and  the  admission  gate,  the  front  portion  of  the  enclosure  being 
used  as  a  refreshment  park  in  which  the  music  from  the  airdome 
piano  or  orchestra  (if  any)  is  heard,  while  the  rear  portion  of  the 
lot  is  the  theater  itself. 

OPERATION 

Studying  Audiences.  The  manager  will  learn  much  about  his 
show  by  watching  his  patrons  as  they  come  out.  It  is  not  necessary 
to  inquire  what  they  think  of  the  show  Comments  will  pa.ss  among 
them  which  may  be  overheard  by  the  manager  and  by  the  casliier 


195 


32  THE  MOTION  PICTURE 

as  they  pass  the  ticket  window,  commenting  favorably  and  un- 
favorably upon  the  film  pictures  which  they  have  seen  a  few  minutes 
before.  In  this  manner  the  manager  may  learn  when  any  particular 
picture  has  favorable  comment,  and  may  endeavor  to  have  his  film 
exchange  supply  more  of  the  same  class;  likewase,  when  any  picture 
has  a  flood  of  unfavorable  comment  among  the  theatergoers  them- 
selves, the  manager  may  try  to  influence  his  film  exchange  to  avoid 
sending  him  that  class  of  subject. 

The  words,  "try  to  influence  his  film  exchange,"  are  chosen 
carefully  to  express  the  true  position  of  the  exhibitor,  or  theater 
manager,  in  the  matter  of  obtaining  film  pictures  acceptable  to  his 
patrons.  The  film  exchanges  as  a  rule  take  all  the  film  pictures  pro- 
duced by  the  particular  manufacturers  from  whom  they  buy.  All 
of  these  film  reels  look  alike  to  the  film  exchange  man,  and  he  would 
like  to  send  them  indiscriminately  to  his  customers,  to  the  exhibitors, 
or  to  theater  managers.  The  service  the  theater  manager  will  get, 
therefore,  w\\\  be  "hit  or  miss"  of  the  film  exchange  stock  of  reels 
unless  some  influence  is  used  by  the  manager  to  govern  the  classes  of 
pictures  furnished  him.  Film  exchanges  are  notoriously  lax  in  the 
matter  of  selecting  pictures  for  particular  theaters.  If  the  film  service 
is  to  be  what  the  manager  desires,  the  deliveries  of  the  film  exchange 
must  be  watched  constantly  and  carefully. 

The  manager  who  has  learned  the  tastes  of  his  audience  should 
consider  their  tastes  as  a  requirement  upon  him  to  obtain  the  pre- 
ferred classes  of  pictures  from  his  film  exchange.  The  responsive- 
ness of  the  audience  in  the  theater  is  one  barometer  of  public  ap- 
proval; the  attitude  and  conduct  of  patrons  leaving  the  theater  is 
another.  The  ticket  sales  will  be  another,  but  this  last  is  not  so  quick 
in  its  indications  of  response. 

AVhen  a  picture  pleases  the  audience,  it  may  be  the  specific 
picture,  or  it  may  be  the  general  class  to  which  the  picture  belongs; 
in  one  neighborhood,  dramatic  and  scenic  may  please  more  than 
comic  or  historical;  in  another  nothing  but  comics  can  draw  the 
crowds  and  send  them  away  smiling. 

The  Program.  \Miether  vaudeville  is  advisable  and  profitable, 
and  whether  the  song  is  a  drawing  card  or  whether  the  audience 
would  rather  have  solid  pictures,  all  may  be  learned  from  watching 
the  house  during  the  performance  and  watching  the  faces  and  com- 


4 


196 


MOTION-PICTURE  THEATER 


33 


merits  of  the  patrons  as  they  pass  out  after  seeing  the  performance. 

Choice  of  a  program  is  a  great  factor  where  the  theater  is  in  a 
competitive  position.  There  is  but  httle  difference  in  expense  between 
a  three-reel  program  and  two  reels  and  a  song. 

Advertising.  A  sign  at  the  door  of  the  theater  may  announce 
the  titles  of  the  films  being  shown,  or  may  announce  merely  that 
motion  pictures  are  being  shown.  It  is  customary  to  announce  the 
titles  of  the  films  if  the  films  can  be  obtained  from  the  film  exchange 


Fig.  6.    A  Title  Poster 

long  enough  in  advance  to  prepare  the  sign,  or  if  posters  are  delivered 
with  the  films.  At  times  it  may  help  business  to  advertise  the  name 
of  the  maker  rather  than  the  name  of  the  film,  or  to  post  the  announce- 
ment as  to  the  nature  of  the  picture,  "A  roaring  farce  tonight,"  or 
"Beautiful  colored  picture  tonight,"  rather  than  a  title  which  might 
not  suggest  the  nature  of  the  film.  In  all  of  these  details  of  his  an- 
nouncement boards  at  the  front  of  the  theater,  the  manager  must 
use  his  judgment  as  applied  to  his  patrons.     Variation  in  signs  is 


197 


34  THE  MOTION  PICTURE 

advisable;  and  always  bear  in  mind  that  the  program,  the  film  pic- 
tures, the  song  and  the  music,  or  vaudeville,  if  any,  if  mentioned 
in  the  theater-front  signs,  must  justify  the  sign  and  fulfil  all  its 
promises. 

Poster  Service.  Title  posters  may  be  obtained  from  the  film 
exchanges  at  a  very  small  cost — five  cents  each  is  the  usual  charge — 
or  they  may  be  obtained  from  companies  making  a  specialty  of 
supplving  title  posters  for  films.  These  come  in  one-sheet  size — 
the  standard  title  poster  size  adopted  by  all  film  makers— and  have 
something  the  appearance  of  the  poster  of  Fig.  6.  The  charge  for 
a  poster  service  consisting  of  a  weekly  shipment  of  posters  for  the 
current  films,  which  the  theater  manager  then  holds  until  he  gets 
the  films  and  ultimately  throws  away  the  posters  which  he  has  received 
for  which  he  never  got  the  films,  is  from  $5  to  $10  per  month. 

In  addition  to  simple  "title  posters"  containing  a  stock  form 
of  border  design  (sometimes  in  color)  and  the  title  of  the  film  printed 
upon  it,  the  film  manufacturers  publish  with  each  film  an  attractive 
colored  poster,  one-sheet  size.  A  quantity  of  these  are  delivered 
to  the  film  exchange  with  every  film  sold,  and  in  turn  the  film  exchange 
will  furnish  them  to  the  exhibitor  to  whom  the  film  is  rented.  As 
to  the  terms  upon  which  the  exhibitor  may  secure  these  posters, 
that  is  a  matter  individual  to  the  film  exchange.  Usually  they  are 
furnished  free  to  the  customers  who  get  the  films  first,  paying  the 
higher  prices  for  the  early  runs  of  the  film.  I^ater  users  of  the  film 
do  not  get  any  posters  because  they  are  all  gone.  The  "title  poster" 
service  is  a  resource  when  the  manufacturer's  more  desirable  picture 
posters  cannot  be  obtained. 

Electric  Signs.  An  electric  sign,  with  a  word  in  letters  formed 
by  electric  lamps,  such  as  "Theater,"  "5c  Theater,"  "^Motion," 
or  "Pictures/'  or  even  "5c,"  can  be  seen  a  long  way  up  and  down 
the  street. 

A  simple  electric  sign  is  illustrated  in  Fig.  7.  This  has  the 
words,  "Theater  5c,"  in  letters  studded  with  electric  lamps.  With 
4-candle-power  lamps  taking  about  12  watts  each,  and  with  electric 
current  at  10  cents  per  kilowatt,  the  cost  of  current  for  operating 
this  sign  four  hours  in  an  evening  would  be  about  fifty  cents.  To 
this  may  be  added  cost  of  lamp  renewals,  interest,  and  depreciation 
on  the  sign,  if  so  desired.    The  cost  of  such  a  sign  is  about  $50. 


198 


Fig.  7.    A  Simple  Electric  Sign 


MOTION-PICTURE  THEATER  35 

Another  type  of  electric  sign  is  shown  in  Fig.  8,  in  which  the 
letters  are  not  studded  with  lamps,  but  in  which  the  lamps  of  the 
sign  form  the  attractive  feature.  The  figure  5c  in  the  middle  of  the 
sign  is  set  with  lamps,  and  the 
zigzag  line  from  the  upper  right- 
hand  comer  to  the  lower  left- 
hand  corner  is  set  with  a  line 
of  lamps.  A  sign  flasher  is  con- 
nected with  this  sign,  lighting  the 
lamps  in  this  order:  The  zigzag  line  represents  a  lightning  flash. 
The  first  lamp  at  the  top  is  lighted,  then  the  next,  and  so  on  until 
about  eight  are  lighted,  then  as  each  lamp  ahead  is  lighted  the  lamp 
earliest  lighted  of  the  eight  is  put  out,  so  that  the  string  of  eight  lamps 
seems  to  move  along  the  zigzag  line.  This  action  is  very  rapid,  and 
the  lightning  flash  crosses  the  sign  very  quickly.  Then  the  5c  is  lighted 
for  a  few  seconds,  then  extinguished  for  a  few  seconds,  and  the  light- 
ning flash  is  repeated,  beginning  the  next  cycle.  The  flashing  of  the 
lamps  is  done  by  a  drum  of  contacts  run  by  a  small  motor.  The 
number  of  lamps  is  about  the  same  as  in  the  sign  of  Fig.  7,  and  the 
cost  of  current  is  about  the  same, 
the  lamps  burning  but  a  part  of 
the  time,  and  the  motor  running 
all  the  time.  The  first  cost  of  the 
sign  is  much  greater. 

In  a  simple  sign  bordered  by 

*:  ^  ''  Fig.  8.    Electric  Sign  with  Flasher 

lamps,    the  lamps  may  be  made 

to  "run  around"  in  the  same  way  that  the  flash  crosses  the  sign  of 
Fig.  8,  adding  to  the  attractiveness  of  an  otherwise  very  plain  sign. 
Announcement  Slides.  The  program  of  the  theater  always  may 
be  announced  by  advertising  announcement  slides.  These  take  the 
form  of  "Pictures  Changed  Daily,"  "Song  Changed  Twice  a  Week," 
"New  Song  Tomorrow,"  "Colored  Picture  Tomorrow  Night," 
"Special  Educational  Show  for  School  Children,  one  hour,  beginning 
at  four  o'clock  Friday,"  all  of  which  are  direct  advertising  slides, 
but  will  not  be  so  considered  by  the  patrons  because  they  pertain 
to  the  show.  Although  they  take  but  a  minute  or  two,  they  may  well 
be  omitted  on  Saturday  night's  rush,  particularly  if  so  doing  will 
put  on  one  more  show  in  the  evening. 


199 


36  THE  MOTION  PICTURE 

"Next  show"  slides  are  of  doubtful  utility,  announcing  the  sub- 
lects  for  tomorrow.  It  is  doubtful  whether  at  any  time  it  is  advisable 
to  announce  the  subjects  for  tomorrow,  if  competitive  theaters  are 
near  by,  unless  the  subject  is  a  special  one  and,  therefore,  specially 
advertised.  AMien  used,  the  "next  show"  slides  must  be  prepared 
by  the  theater  manager  or  projection  operator,  from  day  to  day,  as 
the  titles  are  learned  ahead. 

Printed  Programs.  With  "daylight  pictures" — the  expression 
is  used  to  mean  that  the  lights  of  the  room  are  not  turned  off  while 
the  pictures  are  being  shown — a  printed  program  may  be  given 
to  the  patron  at  the  door.  The  printed  program  always  carries 
advertising  matter,  and  should  be  so  designed  as  to  advertise  the 
theater  properly,  as  well  as  to  serve  its  paid  advertisers. 

Newspapers.  Advertisements  inserted  in  the  newspapers  are 
seldom  profitable  in  the  large  cities;  in  the  smaller  cities,  it  may  be 
found  so;  but  in  the  country  town,  where  the  newspaper  is  a  weekly 
and  everybody  reads  all  of  it,  50c  or  SI  per  week  is  well  spent.  The 
simple  announcement,  with  some  display  line  in  it,  may  or  may  not 
give  the  titles. 

Handbills.  In  the  large  city,  the  theater  located  in  the  residence 
district  will  find  that  the  handbill  will  take  the  place  of  the  newspaper 
in  the  small  toA\'n,  and  cost  but  little  more.  A  thousand  bills,  6  by  9 
inches  in  size,  may  be  had  from  the  local  printer  for  a  price  not  to 
exceed  S2,  and  a  boy,  at  SI  for  the  afternoon,  will  deliver  them.  This 
expense  should  put  a  handbill  into  every  residence  within  five  blocks 
of  the  theater.  Such  a  handbill  should  contain  some  special  announce- 
ment as  an  excuse  for  its  existence;  the  title  and  short  mention  of 
the  nature  of  some  special  film  to  be  featured  will  be  sufficient  excuse; 
or  a  prize  voting  contest,  or  special  program  of  specific  nature. 

Noise  Wagon.  Painted  banners  are  mounted  on  a  wagon — 
sometimes  called  a  "sandwich  wagon" — and  driven  through  the 
streets,  a  bell  being  hung  inside  which  rings  continually,  or  a  dnimmer 
or  l)ugler  being  carried.  Its  utility  is  limited.  Days  when  the  country 
people  are  in  town  form  one  excuse  for  this  advertising  device. 

Feature  Films.  The  manager  should  see  the  film  himself  before 
deciding  to  feature  it.  It  may  be  seen  at  some  other  theater  or  at 
the  film  exchange;  the  film  exchange  will  be  able  to  tell  the  manager 
where  the  film  is  being  shown,  that  he  may  go  there  to  see  it.    The 


200 


MOTION-PICTURE  THEATER  37 

fact  that  a  specific  film  is  being  advertised  largely  by  its  manufac- 
turer is  not  sufficient  basis  for  a  manager  to  decide  to  feature  it  for 
his  patrons,  for  such  advertising  may  not  be  justified  by  the  film,  or 
even  if  so  warranted,  the  film  may  have  real  merit  and  still  not  be 
suited  to  the  tastes  of  the  theater  as  the  manager  understands  them. 

Having  selected  a  feature  film,  advertise  it  only  a  day  ahead, 
both  by  theater-front  signs  and  handbills.  In  addition,  a  printed 
program  for  the  next  night  with  the  feature  film  advertised  may 
be  handed  to  patrons  leaving  the  theater  on  the  night  before  the 
feature  is  put  on.  Be  careful  that  the  word  "Tomorrow"  is  promi- 
nent in  the  theater-front  announcement  which  is  posted  a  day  ahead, 
or  some  patron,  reading  the  sign  carelessly,  may  go  inside  and  be 
disappointed  because  he  did  not  see  the  feature  film  mentioned 
for  the  next  night. 

Special  F^ograms.  An  entire  program  made  up  of  films  of  some 
specific  nature  may  be  called  a  special  program,  and  advertised 
accordingly.  "Biograph  Night"  on  which  nothing  but  biograph 
reels  are  used,  might  strike  the  popular  fancy  of  some  neighborhood, 
while  "Travel  Night"  on  which  the  majority  of  films  are  scenic, 
might  "make  a  hit"  with  another  neighborhood. 

School  Children.  A  special  program  of  films  particularly  pleas- 
ing to  children,  and  to  some  extent  educational  or  travel,  may  be 
given  in  the  afternoon  after  the  close  of  school,  and  the  result  of  the 
experiment  noted.  Special  arrangements  with  the  film  exchange  will 
be  necessary,  and  a  talk  will  be  needed  with  the  educational  or  travel 
films,  otherwise  they  are  usually  too  unfamiliar  to  the  child  mind 
and,  therefore,  dry  and  uninteresting. 

Amateur  Night.  As  a  part  of  one  show  of  the  evening,  amateurs 
are  invited  to  entertain  the  audience,  with  a  time  limit  of  five  minutes 
each;  after  all  have  done  their  acts,  each  walks  upon  the  stage; 
each  patron  in  the  audience  has  been  requested  to  decide  upon  the 
prize-winning  act,  and  when  the  selected  amateur  enters  the  patrons 
favoring  him  applaud.  The  amateur  getting  the  greatest  applause 
is  awarded  the  advertised  prize  of  the  evening.  "Amateur  Night" 
is  usually  made  a  weekly  event  in  theaters  where  it  is  introduced. 

Contests.  This  is  merely  a  specialized  "amateur  night"  in  which 
all  acts  are  limited  to  the  same  nature,  thereby  placing  the  several 
acts  in  direct  contest  with  each  other. 


201 


38  THE  MOTION  PICTURE 

Double  Price.  A  five-cent  theater  may  run  on  Saturday  night 
at  a  ten-cent  admission  fee.  This  not  only  increases  the  gross  receipts 
for  Saturday  evening  but  acts  as  an  advertising  feature  for  the  theater. 
A  better  show  should  be  given,  to  justify  the  double  price,  in  order 
that  the  patrons  may  not  think  the  double  price  is  being  charged 
merely  because  the  manager  can  get  it  on  Saturday.  The  program, 
however,  should  not  require  double  time,  or  there  will  be  no  gain 
by  the  double  price.  It  may  be  slightly  longer  in  time,  and  may 
have  advertisable  differences  in  quality  if  desired. 

The  live  manager  wnll  find  some  excuse  to  make  a  special  noise 
once  in  a  while  to  get  a  few  new  patrons  to  come  to  his  theater  be- 
cause of  the  special  feature  advertised. 

Renting  Films.  Subscribe  for  a  magazine  devoted  to  motion- 
picture  interests,  and  read  the  advertisements  of  the  film  exchanges. 
Select  two  or  three  liberal  advertisers  near  the  theater  and  get  their 
prices.  Films  contracted  for  as  "not  more  than  thirty  days  old" 
will  be  about  the  cheapest,  quality  considered.  In  the  'city,  two 
reels,  daily  change,  should  cost  $20  to  $25  weekly.  This  is  much 
better  than  "one  reel  ten  days  and  one  reel  commercial,"  for  "com- 
mercial" means  "junk"  to  the  exchange  man  If  you  have  film  with 
a  timt  limit,  keep  the  file  of  the  motion-picture  magazine  with  its 
list  of  releases  or  clip  and  file  the  lists  of  releases  and  look  up  every 
film  recei^•ed  to  make  sure  that  the  exchange  man  is  not  giving  you 
film  older  than  your  contract  age.  In  a  small  town,  the  price  to  be 
paid  for  film  will  be  limited  by  the  gross  income,  and  the  manager 
must  shop  around  the  film  exchanges  to  get  the  best  he  can  for  his 
money. 

Get  the  benefit  of  competition  among  film  exchanges  by  learn- 
ing what  others  would  charge  for  the  service  you  are  buying,  but 
never  change  film  exchanges  without  giving  your  own  exchange  a 
chance  to  meet  the  other  fellow's  prices  and  terms. 

Song  Slides.  The  slides  are  rented  from  the  film  exchange, 
although  there  are  some  exchanges  handhng  song  slides  only.  The 
price  is  25  cents  to  $1  for  the  set  of  slides  for  a  week  or  less, 
and  extra  for  the  sheet  music  if  not  returned  with  the  slides. 

Hiring  Employes.  In  the  cities,  singer  and  pianist  may  be 
obtained  in  the  neighborhood,  by  advertising  in  the  daily  papers 
or  on   the  special  program  handbills.     Either  one  should  be  em- 


202 


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MOTION-PICTURE  THEATER  39 

ployed  at  SI  to  $1.50  per  night.  A  drummer  who  is  employed  else- 
where during  the  day  should  have  the  same  price.  Cashier  at  $4 
to  $7  weekly  is  ample  in  the  city.  In  the  small  towns,  these  prices  may 
be  cut  one-half.  The  projection  operator,  with  a  license  and  a  union 
in  the  city,  must  have  $15  for  evenings  only.  In  the  smaller  towns, 
unless  employed  for  the  full  day,  he  may  be  scheduled  for  one-half 
that  price;  this  assumes  that  he  is  employed  during  the  day  elsewhere. 

Automatic  Music.  An  automatic  piano  may  be  rented  or  bought 
— $800  usually  will  buy  one — and  the  perforated  strip  music  may 
be  obtained  from  a  music  exchange  or  "library"  with  daily  or  weekly 
charge  at  a  price  of  $1  to  $2.50  per  month.  The  automatic  piano 
may  furnish  the  only  music  for  an  "all  picture"  show,  or  may  be  used 
early  and  late  in  the  evenings  to  make  die  pianist's  hours  shorter 
and  reduce  the  expense,  besides  being  ready  always  to  furnish  music 
for  a  full  evening  when  the  pianist  fails  to  appear. 

Vaudeville.  The  acts  must  be  booked  from  a  dramatic  booking 
agency;  no  other  method  is  reliable  nor  satisfactory.  A  single  act 
by  a  single  actor  may  be  put  on  at  $25  per  week  and  up.  Any  act 
will  cost  $25  per  actor,  and  up  from  that  price.  If  you  are  rimning 
vaudeville,  by  all  means  keep  posted  on  what  other  theaters  are 
doing,  and  get  acquainted  with  their  booking  agencies,  for  com- 
petition's sake,  to  see  that  you  are  getting  the  best  your  money  will 
buy. 

Splitting  the  Week.  Vaudeville  is  "weekly  change."  In  the  city, 
where  the  patronage  of  a  residence  district  theater  is  limited  to  a 
small  area,  and  in  smaller  cities,  where  a  large  proportion  of  patrons 
are  likely  to  visit  the  theater  oftener  than  one  nighf  in  the  week, 
the  plan  of  "splitting  the  week"  between  two  theaters  is  adopted  to 
give  each  a  change  of  vaudeville  in  the  middle  of  the  week.  AMien 
two  theaters  are  co-operating  thus,  films  as  well  as  vaudeville  acts 
may  be  "split,"  particularly  if  the  theaters  are  in  two  nearby  country 
towns.  Each  theater  hires  a  vaudeville  act  and  a  few  reels  of  film 
for  the  week,  and  the  entire  program  changes  theaters  in  the  middle 
of  the  week.  Booking  agencies  will  arrange  for  "spUt  weeks"  as 
desired. 

Keeping  Accounts.  For  theaters  whose  expenses  and  incomes 
run  into  hundreds  of  dollars  weekly,  a  full  double-entry  set  of  books 
should  be  kept.     For  the  smaller  theaters,  two  books  will  answer 


203 


40 


THE  MOTION  PICTURE 


the  purpose  very  well.  All  theater  accounts  should  be  strictly  cash. 
Since  the  ticket  window  account  is  strictly  cash,  there  can  be  no  good 
business  policy  in  not  having  the  expense  account  run  on  the  same 
basis;  if  the  cash  from  the  income  account  will  not  pay  cash  for  the 
expense  account,  quit  the  business  or  think  of  a  good  reason  why  not. 
For  a  small  theater,  a  little  leather-covered  pocket  memorandum 
book  may  be  used  to  write  down  all  amounts  paid  out  and  received, 
for  any  purpose  whatsoever.  ^Memoranda  of  contracts  and  agree- 
ments may  be  entered  in  this  book.  The  other  book  is  a  book  of 
ruled  pages,  one  for  each  week  of  the  theater's  operation;  perhaps 
a  book  of  fifty-two  pages  would  be  a  convenient  size,  covering  just 
a  year  of  operation.     The  ruling  of  the  pages  of  this  book  may  be 


m 

DAY 

TITLE -/FimS 

TITLE  e^  SONGS 

Kzcnns 

EXPENSES 

SUN. 

RENT 

ELECTRICITY 

MON. 

FILM  RENT 

FIANO  RENT 

TUES. 

SLIDES 

ADVERTISING 

WED. 

EXPRESS 

SALARY-OPERATOR 

THUR 

SINGER 

FIANST 

FRl. 

..  TICKETSaiER 

■       "  DOOR  KEEPER 

SAT. 

■•  USHER 

EXTRAS 

REMARKS: 

ADniSSIOM  ff£CEJFT5 

TOTAL  RECEIPTS 

0THEF7  RECEIPTS 

TOTAL  EXPENSES 

TOTAL  RECEIPTS 

NET  PROFITS 

Fig.  9.     Blank  Form  for  Weekly  Account  of  a  Mot  ion- Picture  Theater 

as  shown  in  Fig.  9,  or  any  modification  of  that  form  which  suits  the 
manager's  fancy.  A  local  printer  would  print  a  thousand  of  these 
on  a  good  quality  of  letter  paper  for  $4,  and  he  would  want  about 
the  same  money  for  fifty-two  of  them,  the  principal  labor  being 
in  the  preparation  of  the  printing  form.  By  having  them  printed, 
the  manager  may  have  his  own  preferred  ruling.  Books  answering 
the  purpose  may  be  bought  for  a  year's  business  for  a  dollar  or  less. 
Each  day  the  titles  of  the  films  may  be  entered  on  the  page. 
This  is  to  prevent  running  the  same  film  twice  without  a  proper  inter- 


204 


MOTION-PICTURE  THEATER  41 

val  between,  as  might  result  from  an  error  of  the  fihn  exchange, 
or  from  a  change  in  fihn  exchanges.  The  songs  are  recorded  Hke- 
wise.  Fihns  and  songs  which  seemed  to  be  "hits"  with  the  audience 
may  be  marked  with  a  cross  and  asked  for  from  the  exchange  as 
specials,  "repeated  by  request"  for  advertising  effect. 

The  ticket-window  receipts  and  other  receipts  should  be  entered 
in  the  pocket  memorandum  book,  and  may  be  noted  on  the  back  of 
the  weekly  sheet  until  the  end  of  the  week,  when  the  totals  may  be 
entered  on  the  face  of  the  weekly  sheet,  and  the  net  profits  for  the 
week  may  be  determined. 

An  extra  sheet  at  the  back  of  the  book  may  have  entered  upon 
it  in  each  space  the  total  of  the  same  space  on  all  the  weekly  sheets. 
The  net  profits  for  the  year  thus  may  be  shown,  as  well  as  a  classifica- 
tion of  the  expenses  for  the  year. 

Dull  Season.  In  summer-time  in  the  country,  the  farmers  are 
too  busy  to  come  to  town  except  on  Saturday  afternoon.  In  summer- 
time in  the  city  the  people  go  to  the  parks  or  sit  on  their  front  porches. 
"In  the  good  old  summer-time,"  what  is  the  picture-theater  manager 
to  do?  If  he  worked  hard  during  the  winter,  and  expects  to  do  the 
same  next  winter,  it  may  be  to  his  advantage  ultimately  to  shut  up 
the  place  for  July  and  August,  pay  the  rent  on  the  vacant  house, 
and  take  a  thorough  rest.  A  little  painting  and  polishing  may  be 
done  during  this  interval,  and  he  can  open  the  house  with  a  big  whoop 
and  hurrah  about  September  1. 

Another  method  is  to  make  the  show  straight  pictures,  and  cut 
the  expense  sheet  to  the  absolute  minimum;  perhaps  the  ticket  win- 
dow will  be  able  to  get  enough  small  coin  to  pay  the  operating  charges. 
Nothing  but  a  shopper's  theater  in  the  shopping  center  of  a  large 
city  can  run  a  summer  show  at  winter  profits.  This  excepts  the  pic- 
ture show  which  is  a  part  of  a  summer  amusement  park,  and  also 
the  airdome.  They  are  shows  which  flourish  in  the  summer-time 
only. 

A  study  of  the  weekly  account  sheets  as  summer  approaches 
will  show  the  dwindling  profits.  The  manager  then  must  decide 
what  his  policy  for  thf^  summer  will  be. 

Tickets  and  Chopper.  Tickets  will  be  furnished  by  the  film 
exchanges,  at  15  to  20  cents  per  thousand,  in  rolls.  They  are  sold 
by  the  cashier,  and  the  proper  amount  of  money  which  the  cashier  is 


205 


42  THE  MOTION  PICTURE 

to  turn  over  to  the  manager  may  be  determined  by  noting  the  number 
of  the  end  ticket  of  the  roll  before  the  show  and  subtracting  it  from 
the  end  ticket  of  the  roll  after  the  show,  multiplying  the  difference 
by  the  price  of  admission.  This  number  of  tickets  should  be  found 
in  the  "ticket  chopper,"  or  ticket  box,  and  also  the  numbers  of  the 
tickets  in  the  box  should  correspond,  if  they  were  examined. 

The  ticket  chopper  takes  its  name  from  its  function.  It  muti- 
lates the  ticket  which  is  dropped  into  it  in  such  manner  that  it  may 
not  be  used  again.  Some  choppers  slit  them  into  ribbons,  while 
others  punch  holes  in  them,  passing  the  tickets  into  one  box  and  the 
small  bits  from  the  holes  into  another  receptacle.  In  either  case, 
the  ticket  if  reclaimed  from  the  box  by  fraud  would  not  be  suitable 
for  use  again.  Where  a  ticket  box  which  does  not  chop  is  used,  the 
manager  should  give  his  personal  attention  to  destroying  the  tickets 
each  day,  preferably  by  burning  them.  Every  ticket  that  is  not 
destroyed  by  the  manager  himself  means  a  possible  loss  of  five  cents, 
for  it  might  be  used  at  the  door  again,  even  though  its  destruction 
is  intrusted  to  another. 

Change  the  color  every  day,  having  several  rolls  of  different 
color,  and  using  sometimes  one  and  sometimes  another.  A  ticket 
of  the  wrong  color  dropped  into  the  ticket  box  will  reveal  an  irregular- 
ity which  may  lead  to  important  discoveries  in  the  accounting  system. 

A  quiet  and  accurate  "head  count"  of  people  entering  the  theater 
door  on  an  occasional  night,  compared  with  ticket  numbers  and 
cashier's  receipts,  will  help  to  keep  this  most  vital  detail  of  the  theater 
under  control. 

The  manager  sometimes  is  confronted  with  a  class  of  patrons 
who  stay  in  the  theater  longer  than  one  show,  and,  therefore,  longer 
than  one  admission  fee  justifies.  AMien  the  house  is  "holding  out" 
the  crowds,  each  patron  of  this  class  reduces  the  profits  of  the  theater. 
One  method  of  handling  this  problem  is  to  take  tickets  at  the  door 
until  the  first  show  begins;  after  that,  do  not  take  up  the  whole  ticket, 
but  tear  off  about  one-quarter,  permitting  the  patron  to  retain  the 
large  part  of  the  ticket.  This  gives  each  patron  entering  during  the 
show  a  torn  ticket.  Between  shows,  collect  tickets  from  all  in  the 
theater.  Those  having  no  torn  tickets  must  have  seen  the  entire 
performance,  and  should  pay  another  admission  fee  or  leave  the 
theater. 


206 


r 


MOTION-PICTURE  THEATER  43 

Side  Lines  for  Profit.  The  patron  has  a  sentiment  agaitist  any 
form  of  advertising  in  the  theater.  For  the  theater  in  a  competitive 
position,  it  is  a  good  plan  to  avoid  all  semblance  of  advertising  inside 
the  theater — upon  the  walls  or  upon  the  picture  screen,  either  drop 
curtain  or  lantern  slides.  The  tone  of  the  theater  is  improved  by 
leaving  the  show  clean  and  free  from  advertising  of  any  kind,  par- 
ticularly if  the  competing  theaters  offer  objectionable  advertising 
matter.  At  the  same  time,  the  big  vaudeville  houses  of  the  cities  use 
their  advertising  drop  curtain  before  the  performance  and  put  ad- 
vertising matter  in  their  street  scenes.  Also,  the  legitimate  theaters 
sell  candy  in  the  auditorium  between  the  acts  and  before  the  per- 
formance begins.  The  manager  must  judge  his  people  on  these 
points  and  handle  his  advertising  accordingly. 

Following  are  a  few  plans  available  for  increasing  the  revenue 
of  a  theater  beyond  ticket-window  receipts: 

Mall  Posters.  This  plan  is  borrowed  from  the  street-car  prac- 
tice of  assigning  a  wall  space  for  advertising  matter.  The  street- 
car practice  is  not  objectionable,  because  the  space  is  well  chosen 
and  advertising  matter  is  confined  strictly  to  the  selected  space. 
As  to  its  application  in  any  specific  theater,  the  sentiment  of  the 
patrons  must  be  judged.  Many  things  will  pass  in  a  small  country 
town  which  would  not  be  endured  by  patrons  in  a  city. 

Advertising  Drop  Curtain.  The  picture  screen  is  an  unsightly 
object  in  the  theater  when  there  is  no  projected  picture  upon  it. 
The  appearance  of  the  room  is  improved  greatly  during  the  inter- 
mission by  lowering  an  ornamental  drop  curtain  oyer  the  picture 
screen.  This  drop  curtain  may  contain  advertising  matter.  It  should 
be  well  put  on — at  the  expense  of  the  advertising  client — and  a 
liberal  price  charged. 

Advertising  Slides.  Advertising  slides  bear  advertising  matter 
for  the  advertising  patron,  and  such  slides  are  thrown  upon  the  screen 
along  with  the  set  of  announcement  slides  with  which  the  program 
begins,  before  the  motion  pictures  start.  A  single  advertising  slide 
is  hardly  objectionable  anpvhere,  but  too  many  will  ruin  the  show. 

In  connection  with  advertising  slides,  insist  that  the  slides  be 
pleasing  in  appearance  and  brief  in  words.  Of  course  the  cost  of 
making  the  slide  is  paid  by  the  advertiser.  Remember  that  the 
same  people  come  to  your  theater  every  week,  and  insist  upon  a 


207 


44  THE  MOTION  PICTURE 

weekly  change  of  the  advertising  sHde  also.  The  patron  who  comes 
the  second  time  comes  to  see  a  different  show.  Not  only  the  adver- 
tising slides  of  the  paid  advertiser  must  be  changed  often,  but  the 
announcement  slides  which  are  in  substance  advertising  slides  of 
the  theater  itself,  must  be  ehanged.  Old  slides  which  have  been 
on  the  shelf  a  few  weeks  may  be  "run"  again  as  new  from  time  to 
time,  but  change  the  slide  program  for  the  same  reason  that  you  change 
the  picture  program  and  the  song  program.  Your  people  want  some- 
thing: new  all  the  time. 

Don't  let  any  patron  get  the  thought  that  the  manager  is  asleep 
or  that  the  theater  is  not  keeping  up  with  every  other  theater  in  the 
land. 

Program  Advertising.  This  is  a  practice  set  by  the  large  theaters. 
No  theater  program  is  complete  without  advertising  matter  upon  it, 
and  this  can  be  obtained  from  local  merchants  at  prices  which  will 
assist  in  paying  tb.e  expense  of  printing  the  theater's  program,  or 
even  yield  a  profit. 

In  soliciting  program  advertising,  remember  that  the  adver- 
tisement will  increase  the  size  and  cost  of  the  program,  so  that  the 
price  must  be  still  greater  than  the  difference  in  cost  which  the  printer 
will  make.  The  difference  in  cost  may  be  learned  by  getting  prices 
from  the  printer  for  the  programs  with  and  without  advertising. 

Handbills.  The  weekly  handbill  is  worth  its  cost  in  any  city 
show.  The  cost  may  be  reduced  by  carrjdng  the  advertisement  of 
a  local  merchant,  or  two  or  three  in  different  lines  of  business,  for 
a  ])rice  in  excess  of  the  added  cost  of  the  bills  at  the  printer's.  In 
addition,  a  proportion  of  the  distributing  charge  is  added  to  the 
price  for  the  merchant,  always  keeping  the  price  to  him  lower  than 
what  it  would  cost  him  to  print  and  distribute  bills  of  his  own. 

Candij  Kid.  The  practice  of  selling  candy  in  theaters  before 
and  between  acts  is  well  established.  Remember  in  this  connection 
that  the  patrons  come  to  the  theater  to  beamused.  The  candy  vendor 
can  help  much  in  their  entertainment  if  his  "act"  is  studied.  One 
successfid  candy  vendor  waits  only  until  the  old  crowd  is  out  and 
then  as  soon  as  the  new  patrons  start  in  he  walks  before  the  picture 
screen  and  says  something  like  this:  "I  know,  ladies  and  gentlemen, 
that  you  have  come  here  tonight  for  a  little  fun,  sport  and  amuse- 
ment, and  I  am  going  to  add  to  your  fun  just  as  much  as  I  possibly 


208 


MOTION-PICTURE  THEATER  45 

can;  I  have  tonight  a  package  of candy  which  I  am  selling  for 

five  cents;  as  I  pass  up  the  aisle  please  have  your  change  ready." 
He  passes  up  the  aisle  with  his  basket  as  soon  as  the  aisle  is  clear, 
selling  candy  and  making  remarks  to  entertain  the  crowd:  "Don't 
be  afraid  to  buy  it;  it's  worth  the  money;"  "The  young  man  takes 
two  packages  because  the  young  lady  knows  it's  good;"  "Every 
package  guaranteed  to  send  you  home  fat  and  happy;"  "After  you 
eat  it,  if  you  don't  like  it,  give  it  back  and  I'll  refund  the  nickel;" 
when  the  show  starts  before  he  has  finished  his  trip,  he  says,  "Keep 
your  eyes  on  the  pictures  and  hand  me  your  money."  ^^our  people 
have  come  to  your  theater  to  be  entertained;  your  candy  vendor  is 
making  the  intermission  seem  shorter  and  is  positively  adding  to 
their  entertainment. 

Avoid  the  error  of  giving  the  candy  vendor  too  much  time. 
An  intermission  of  eleven  minutes  has  been  observed  and  reported, 
"to  allow  the  candy  man  to  distribute  his  free  samples,  make  a 
second  tour  of  the  audience  to  sell  his  confectionery,  then  a  third  tour 
to  sell  some  songs."  Not  only  will  the  audience  resent  the  delay  to 
the  pictures,  but  the  theater  may  actually  lose  money.  When  the 
house  is  running  crowded,  and  patrons  are  waiting  at  the  door,  the 
number  of  tickets  sold  depends  upon  the  speed  with  which  those 
inside  may  be  shown  the  entire  program,  that  they  may  leave  and 
make  room  for  others.  A  300-seat  house,  at  5-cent  admission,  run- 
ning a  45-minute  program,  inider  crowded  conditions,  is  making 
$15  for  each  program,  or  about  33  cents  per  minute  while  the  pictures 
are  on  the  screen.  Assuming  that  the  candy  vendor  will  be  able  to 
sell  fifty  packages  of  candy  at  five  cents  each — a  phenomenal  sale 
for  so  small  a  house — and  at  a  profit  of  two  cents  each  to  the  theater, 
then  for  that  SI  profit  on  the  candy  he  is  entitled  to  just  three  minutes' 
intermission. 

To  extend  the  intermission  one  minute  is  to  lose  more  money 
at  the  ticket  window  than  is  made  at  the  candy  basket.  ^Mien  the 
theater  manager  understands  this  clearly,  he  will  be  in  possession 
of  a  fundamental  principle  which  applies  to  all  other  side  lines  for 
profit:  Only  when  the  side  line  does  not  decrease  the  ticket  window 
receipts,  only  when  it  leaves  thtvi  unchanged  or  actually  increases 
them,  may  it  be  considered  as  desirable  or  profitable. 

Slot  Machines.    The  lobby,  or  entrance  of  the  theater  in  front 


209 


46  THE  MOTION  PICTURE 

of  the  partition,  offers  space  for  a  few  compact  automatic  vending 
machines,  if,  in  the  manager's  best  judgment,  such  a  plan  is  advisable. 
If  the  police  regulations  of  the  town  will  permit,  an  automatic  vend- 
ing machine  may  stand  on  the  sidewalk  at  each  side  of  the  theater, 
just  in  the  foot  square  of  sidewalk  space  at  the  end  of  the  theater's 
side  walls. 

Sheet  Music  Sales.  It  is  a  favor  to  many  patrons  to  advise  them 
where  sheet  music  of  the  song  may  be  obtained.  An  announcement 
slide,  "The  song  on  our  program  is  always  for  sale  at  our  ticket  win- 
dow," has  no  objection  and  does  not  seem  advertising  matter  because 
it  pertains  to  the  theater. 

Refreshment  Annex.  In  the  airdome,  the  refreshment  business 
is  so  much  associated  with  the  motion-picture  business,  and  they  are 
so  mutually  helpful  to  each  other  that  they  usually  are  nui  in  con- 
junction, each  to  boost  the  other.  In  the  motion-picture  winter 
theater,  the  relation  cannot  be  so  boldly  emphasized  or  the  depart- 
ure from  custom  will  be  noted  and  adversely  commented  upon,  but 
a  candy  store  and  soda  foinitain  located  near  a  motion-picture  theater 
will  do  a  larger  business  than  if  the  theater  were  not  there. 


210 


i 


o  _ 

|i 


H  3  2 

«    ^^ 

a,  .2  >■ 


2:2 

«  o 

W  ^ 
O 


SCENE  FROM  PHOTOPLAY,  "THE  LAST  APPEAL" 

Courtesy  of  Independent  Mating  Pictures  Co.,  New  York 


I 


ELECTRICAL  PRINCIPLES 


In  the  management  of  a  motion-picture  machine  and  theater 
the  operator,  even  if  he  be  well  versed  in  the  practical  methods  of 
running  circuits  for  his  machine,  finds  that  he  needs  a  knowledge 
of  the  elementary  principles  of  electricity  and  some  clear  conception 
of  how  the  electric  current  behaves  in  various  types  of  circuits.  It 
must  be  borne  in  mind,  therefore,  that  only  material  deemed  perti- 
nent to  the  case  has  been  included  in  this  book.  Those  desiring 
more  information  are  referred  to  any  standard  text. 

ELECTRICITY  IN  MOTION— ELECTRICAL  CURRENTS 

Magnetic  Effect  Due  to  a  Charge  in  Motion.  An  electrical 
charge  at  rest  produces  no  magnetic  effect  whatever.  This  can  be 
proved  by  bringing  a  charged 
body  near  a  compass  needle 
or  suspended  magnet.  It  will 
attract  both  ends  equally  well 
by  virtue  of  the  principle  of 
electrostatic  induction.  If  the 
effect  were  magnetic,  one  end 
should  be  repelled  and  the 
other  attracted.  Again,  if  a 
sheet  of  zinc,  aluminum,  or 
copper  is  inserted  between  the 
deflected  needle  and  the  charge,  all  effect  which  was  produced  upon 
the  needle  by  the  charge  will  be  cut  off,  for  the  metallic  sheet  will 
act  as  an  electric  screen.  But  if  such  a  metal  screen  is  inserted  be- 
tween a  compass  needle  and  a  magnet,  its  insertion  has  no  effect  at 
all  on  the  magnetic  forces. 

If,  however,  a  charged  Leyden  jar  is  discharged  through"  a' coil 
which  surrounds  an  unmagnetizerl  Icnitting  needle  in  the  manner 
showai  in  Fig.  1,  the  needle  will  be  found,  after  the  discharge,  to  have 
become  distinctly  magnetized. 

Copyright,  1911,  by  American  School  of  Correspondence. 


Fig.   1.     Magnetic  Effect  of  Electric  Current 


213 


2  THE  MOTION  PICTURE 

This  experiment  demonstrates  the  existence  of  some  connection 
between  electricity  and  magnetism.  Just  what  this  connection  is, 
is  not  yet  known  with  certainty;  but  it  is  known  that  magnetic  effects 
are  always  observable  near  the  path  of  a  moving  electrical  charge, 
while  no  such  effects  can  ever  be  observed  near  a  charge  at  rest. 

An  electrical  charge  in  motion  is  called  an  electrical  current,  and 
the  presence  of  such  current  in  a  conductor  is  most  commonly  de- 
tected by  the  magnetic  effect  which  it  produces. 

Galvanic  Cell.  When  a  Leyden  jar  is  discharged,  but  a  very 
small  quantity  of  electricity  passes  through  the  connecting  wires, 
since  the  current  lasts  but  a  small  fraction  of  a  second.  If  we  could 
keep  the  current  flowing  continuously  through  the  wire,  we  should 
expect  the  magnetic  effect  to  be  more  pronounced. 
This  might  be  done  by  discharging  Leyden  jars 
in  rapiil  succession  through  the  wire.  In  1786, 
.however,  Galvani,  an  Italian  anatomist  at  the 
University  of  Bologna,  accidently  discovered  that 
there  is  a  chemical  method  for  producing  such 
a  continuous  current.  His  discovery  was  not 
understood,  however,  until  Volta,  professor  of 
physics  at  Como,  devised  an  arrangement  which 
is  now  known  sometimes  as  the  voltaic,  some- 
simpic         times  as  the  qalvanic  cell. 

Galvanic  Cells  "^  ....,„ 

Such  a  cell  consists  in  its  simplest  form  of  a 
strip  of  copper  and  a  strip  of  zinc  immersed  in  dilute  sulphuric 
acid,  Fig.  2.  If  the  wires  leading  from  the  copper  and  the  zinc 
are  connected  for  a  few  seconds  to  the  end  of  the  coil  of  Fig.  1, 
when  an  unmagnetized  needle  lies  within  this  coil,  the  needle  will 
be  found  to  be  much  more  stronglv  mafjnetized  than  it  was  when 
the  Leyden  jar  was  discharged  through  the  coil.  Or,  if  the  wire 
connecting  the  copper  and  zinc  is  simply  held  above  the  needle 
ill  the  manner  shown  in  Fig.  3,  the  latter  will  be  found  to  be 
strongly  deflected.  It  is  evident  from  these  experiments  that  the 
wire  which  connects  the  terminals  of  a  galvanic  cell  carries  a  cur- 
rent of  electricity.  Historically,  the  second  of  these  experiments, 
performed  by  the  Danish  physicist  Oersted  in  1819,  preceded  the 
discovery  of  the  magnetizing  effect  of  currents  upon  needles.  It 
created  a  great  deal  of  excitement  at  the  time  because  it  was  the  first 


214 


ELECTRICAL  PRINCIPLES 


clew  which  had  been  found  to  a  relationship  between  electricity  and 
magnetism. 

It  might  be  inferred  from  the  above  experiments  that  the  two 
plates -of  a  galvanic  cell  when  not  connected  by  a  wire  carry  static 


Fig.  3.     Magnetic  Effects  of  Current 

positive  and  negative  charges  just  as  do  the  two  coats  of  a  Leyden 
jar  before  it  is  discharged  through  the  wire.  This  inference  can  be 
easily  verified  with  an  electroscope. 

Thus,  if  a  metal  plate  A,  Fig.  4,  covered  with  shellac  on  its 
lower  side  and  provided  with  an  insulating  handle,  is  placed  upon  a 
similar  plate  B  which  is  in  contact  with  the  knob  on  an  electroscope; 
and  if  the  copper  plate,  for  example, 
of  a  galvanic  cell  is  connected  to  A 
and  the  zinc  to  B;  then,  when  the 
connecting  wires  are  removed  and 
the  plate  A  lifted  away  from  B,  the 
leaves  of  the  electroscope  will  di- 
verge and  when  tested  will  be  found 
to  be  negatively  charged.  If  the 
deflection  observed  in  the  leaves  of 
the  electroscope  is  too  small  for  the 
purposes  of  demonstration,  the  con- 
ditions can  be  bettered  by  using  a 

battery  of  from  five  to  ten  cells  instead  of  the  single  cell.  If,  how- 
ever, the  plates  A  and  B  are  sufficiently  large — say,  3  or  4  inches 
in  diameter — and  if  their  surfaces  are  very  flat,  a  single  cell  will  be 
found  to  be  sufficient.  If,  on  the  other  hand,  the  copper  plate  is 
connected  to  B  and  the  zinc  to  A  in  the  above  experiment,  the  elec- 


Fig.  4.     Static  Charges  on  Plates 
of  Galvanic  Cell 


215 


4  THE  MOTION  PICTURE 

troscope  will  be  found  to  be  positively  charged.  This  shows  clearly 
that  the  copper  plate  possesses  a  positive  electrical  charge,  while 
the  zinc  plate  possesses  a  negative  charge,  these  charges  originating 
in  the  chemical  action  within  the  galvanic  cell. 

In  this  experiment  the  two  metal  plates  separated  by  shellac 
constitute  an  electrical  condenser  which  is  charged  positively  on 
one  side  and  negatively  on  the  other  by  connecting  it  with  the  two 
plates  of  the  galvanic  cell,  in  precisely  the  same  way  in  which  a 
Leyden  jar  is  charged  by  connecting  its  two  coats  one  to  one  terminal 
and  the  other  to  the  other  terminal  of  a  static  machine.  The  poten- 
tial of  the  plate  B  is  increased  by  moving  A  away  from  it.  This 
device  makes  it  possible  to  detect  very  small  potential  differences. 

Comparison  of  a  Galvanic  Cell  and  Static  Machine.  If  one  of 
the  terminals  of  a  galvanic  cell  is  touched  directly  to  the  knob  of 
the  gold-leaf  electroscope  without  the  use  of  the  condenser  plates 
A  and  B  of  Fig.  4,  no  divergence  of  the  leaves  can  be  detected;  but 
if  one  knob  of  a  static  machine  in  operation  were  so  touched,  the 
leaves  would  be  throwTi  apart  very  violently.  Since  we  have  seen 
that  the  divergence  of  the  leaves  is  a  measure  of  the  potential  of  the 
body  to  which  they  are  connected,  we  learn  from  this  experiment  that 
the  chemical  actions  going  on  in  a  gah  anic  cell  are  able  to  produce 
between  its  terminals  but  very  small  potential  differences  in  com.- 
parison  with  that  produced  by  the  static  machine  between  its  ter- 
minals. As  a  matter  of  fact,  the  potential  difference  between  the 
terminals  of  the  cell  is  but  one  volt,  while  that  between  the  terminals 
of  an  electrical  machine  may  be  several  hundred  thousand  volts. 

On  the  other  hand,  if  the  knobs  of  the  static  machine  are  con- 
nected to  the  ends  of  the  wire  shown  in  Fig.  3,  and  the  machine 
operated,  the  current  will  not  be  large  enough  to  produce  any  ap- 
preciable effect  upon  the  needle.  Since,  under  these  same  circum- 
stances the  galvanic  cell  produced  a  very  large  effect  upon  the  needle, 
we  learn  that  although  the  cell  develops  a  much  smaller  p.  d.  than 
does  the  static  machine,  it  nevertheless  sends  through  the  wire  a 
very  much  larger  amount  of  electricity  per  second.  This  means 
merely  that  the  chemical  actions  which  are  going  on  within  the  cell 
are  able  to  recharge  the  plates  when  they  become  discharged  through 
the  electric  wire,  far  more  rapidly  than  is  the  static  machine  able  to 
recharge  its  terminals  after  they  have  once  been  discharged. 


216 


ELECTRICAL  PRINCIPLES 


Shape  of  Magnetic  Field  about  a  Current.  If  we  place  the  wire 
which  connects  the  plates  of  a  galvanic  cell  in  a  vertical  position, 
Fig.  5,  and  explore  with  a 
compass  needle  the  shape  of 
the  magnetic  field  about  the 
current,  we  find  that  the  mag- 
netic lines  are  concentric  cir- 
cles lying  in  a  plane  perpen- 
dicular to  the  wire  and  having 
the  wire  as  their  common 
center.  If  we  reverse  the 
direction  of  the  current,  we 
find  that  the  direction  in  which 
the  compass  needle  points 
reverses  also.  If  the  current 
is  very  strong,  say  40  amperes, 

this  shape  of  the  field  can  be  shown  by  scattering  iron  filings  on  a 
plate  through  which  the  current  passes,  in  the  manner  shown  in  Fig.  5. 
The  relation  between  the  direction  in  which  the  current  flows  and 
the  direction  in  which  the  positive  end  of  the  needle  points — this  is 
by  definition,  the  direction  of  the  magnetic  field — is  given  in  the 
following  rule:  If  the  right  hand  grasps  the  wire  as  in  Fig.  G,  so 
that  the  thumb  points  in  the  direction  in  which  the  positive  electricity 
is  moving,  that  is,  in  the  direction  from  the  copper  toward  the  zinc, 
then  the  magnetic  lines  encircle  the  wire  in  the  same  direction  as  do 


Fig.  5.     Magnetic  Field  Around  a  Conductor 


Fig.  6.     Right-Hand  Screw  Rule  for 
Direction  of  Magnetic  Field 

the  fingers  of  the  hand.  Another  way  of  stating  this  rule  is  as  follows: 
The  relation  between  the  direction  of  the  current  in  a  wire  and  the  di- 
rection of  the  magnetic  lines  aboid  it,  is  the  same  as  the  relation  be- 
tween the  direction  of  the  forivard  motion  of  a  right-handed  screw 
and  the  direction  of  rotation  when  it  is  being  driven  in.  In  this  form 
the  rule  is  known  as  the  right-hand  screw  rule. 


217 


6  THE  MOTION  PICTURE 

Measurement  of  Electrical  Currents.  Electrical  currents  are, 
in  general,  measured  by  the  strength  of  the  magnetic  effect  which 
they  are  able  to  produce  under  specific  conditions.  Thus,  if  the 
wire  carrying  a  current  is  wound  into  circular  form  as  in  Fig.  7,  the 
right-hand  screw  rule  shows  us  that  the  shape  of  the  magnetic  field 
at  the  center  of  the  coil  is  similar  to  that  shown  in  the  figure.  If, 
then,  the  coil  is  placed  in  a  north-and-south  plane  and  a  compass 
needle  is  placed  at  the  center,  the  passage  of  the  current  through 
the  coil  tends  to  deflect  the  needle  so  as  to  make  it  point  east  and 
west.  The  amount  of  deflection  under  these  conditions  is  taken  as 
the  measure  of  current  strength.  The  unit  of  current  is  called  the 
ampere  and  is,  in  fact,  approximately  the  same  as  the  current  which, 
flowing  through  a  circular  coil  of  three  turns  and  10  centimeters 
radius,  set  in  a  north-and-south  plane,  will  produce  at  Washington 


Fig.  7.     Plotting  Field  About  Circular  Conductor 

a  deflection  of  45  degrees  in  a  small  compass  needle  placed  in  its  cen- 
ter, as  in  Fig.  7.  Nearly  all  current-measuring  instruments,  com- 
monly called  ammeters,  consist  essentially  either  of  a  small  magnet 
suspended  at  the  center  of  a  fixed  coil  as  in  Fig.  7,  or  of  a  movable 
coil  suspended  between  the  poles  of  a  fixed  magnet.  The  passage  of 
the  current  through  the  coil  produces  a  deflection,  in  the  first  case, 
of  the  magnetic  needle  with  reference  to  the  fixed  coil,  and  in  the 
second  case,  of  the  coil  with  reference  to  the  fixed  magnet.  If  the 
instrument  has  been  suitably  calibrated,  the  amount  of  the  deflection 
gives  at  once  the  strength  of  the  current  in  amperes. 

Electromotive  Force  and  Its  Measurements.  The  potential 
difference  which  a  galvanic  cell  or  other  generator  of  electricity  is 
able  to  maintain  between  its  terminals  when  these  terminals  are  not 
connected  by  a  wire,  i.  e.,  the  total  electrical  pressure  which   the 


218 


ELECTRICAL  PRINCIPLES  7 

generator  is  capable  of  exerting,  is  commonly  called  its  electromotive 
force,  or  e.  m.  f.  The  e.  m.  f  of  an  electrical  generator  may  then  be 
defined  as  its  capacity  for  producing  electrical  pressure,  or  p.d.  This 
p.  d.  might  be  measured  by  the  deflection  produced  in  an  electroscope, 
or  other  similar  instrument,  when  one  terminal  was  connected  to 
the  case  of  the  electroscope  and  the  other  terminal  to  the  knob. 
Potential  differences  are  in  fact  measured  in  this  way  in  all  so-called 
electrostatic  voltmeters,  which  are 
now  coming  more  and  more  into 
use. 

The  more  common  type  of 
potential  difference  measurers,  so- 
called  voltmeters,  consists,  however, 
of  an  instrument  made  like  an 
ammeter,  save  that  the  coil  of  wire 
is  made  of  an  enormous  number  of 
turns  of  extremely  fine  wire,  so  that 
it  carries  at  very  small  current. 
The  amount  of  current  which  it 
does  carry,  however,  and  therefore 
the  amount  of  deflection  of  its 
needle,  is  taken  as  proportional  to 
the  difference  in  electrical  pres- 
sure existing  between  its  ends  when 
these  are  touched  to  the  two  points 
whose  p.  d.  is  sought.  The  prin- 
ciple underlying  this  type  of  voltmeter  will  be  better  understocxJ 
from  a  consideration  of  the  following  water  analogy.  If  the  stop- 
cock K  Fig.  8,  in  the  pipe  connecting  the  water  tanks  C  and  D  is 
closed,  and  if  the  water  wheel  A  is  set  in  motion  by  applying  a 
weight  W ,  the  wheel  will  turn  until  it  creates  such  a  difference  in  the 
water  levels  between  C  and  D  that  the  back  pressure  against  the 
left  face  of  the  wheel  stops  it  and  brings  the  weight  W  to  rest.  In 
precisely  the  same  way,  the  chemical  action  within  the  galvanic 
cell  whose  terminals  are  not  joined,  Fig.  9,  develops  positive  and 
negative  charges  upon  these  terminals,  that  is,  creates  a  p.  d.  between 
them,  until  the  back  electrical  pressure  through  the  cell  due  to  this 
p.  d.  is  sufficient  to  put  a  stop  to  further  chemical  action. 


Fig.   8.     Hydrostatic  Analogy  of 
Potential  Difference 


219 


8 


THE  MOTION  PICTURE 


Now,  if  the  water  resen-oirs,  Fig.  S,  are  put  in  communication 
by  opening  the  stop-cock  K,  the  difference  in  level  between  C  and  D 
will  begin  to  fall,  and  the  wheel  will  begin  to  build  at  up  again.  But 
if  the  carrying  capacity  of  the  pipe  a  b  is  small  in  comparison  with  the 
capacity  of  the  wheel  to  remove  water  from  D  and  to  supply  it  to  C, 
then  the  difference  of  level  which  permanendy  exists  between  C  and 
D  when  K  is  open  will  not  be  appreciably  smaller  than  when  it  is 
closed.  In  this  case  the  current  which  flows  through  AB  may 
obviously  be  taken  as  a  measure  of  the  difference  in  pressure  which 
the  pump  is  able  to  maintain  between  C  and  D  when  K  is  closed. 

In  precisely  the  same  way,  if  the  terminal 
C  and  D  of  the  cell.  Fig.  9,  are  connected  by 
attaching  to  them  the  terminals  a  and  b  of 
any  conductor,  they  at  once  begin  to  discharge 
through  this  conductor,  and  their  p.  d.,  there- 
fore, begins  to  fall.  But  if  the  chemical 
action  in  the  cell  is  able  to  recharge  C  and 
D  very  rapidly  in  comparison  with  the  ability 
of  the  wire  to  discharge  them,  then  the  p.  d. 
between  C  and  D  will  not  be  appreciably 
lowered  by  the  presence  of  the  connecting 
conductor.  In  this  case  the  current  which 
flows  through  the  conducting  coil,  and,  there- 
fore, the  deflection  of  the  needle  at  its  center,  may  be  taken  as  a 
mejisure  of  the  electrical  pressure  developed  by  the  cell,  that  is,  of 
the  p.  d.  between  its  unconnected  terminals. 

The  common  voltmeter  is,  then,  exactly  like  an  ammeter, 
save  that  its  coil  offers  so  high  a  resistance  to  the  passage  of 
electricity  through  it  that  it  does  not  assist  appreciably  in  discharg- 
ing, that  is,  in  reducing  the  p.  d.  between  the  points  to  which  it  is 
connected. 

The  unit  of  p.  d.  may  be  taken  for  practical  purposes  as  the 
electrical  pressure  produced  by  a  simple  galvanic  cell  consisting  of 
zinc  and  copper  immersed  in  dilute  sidphuric  acid.  It  is  named  a 
volt  in  honor  of  Volta. 

Electromotive  Forces  of  Galvanic  Cells.  ^Mien  a  voltmeter  of 
any  sort  is  connected  to  the  terminals  of  a  galvanic  cell,  it  is  found 
that  the  deflection  produced  is  alt(jgether  independent  of  the  shape 


Fig.  9.     Principle  of  Com- 
mon Voltmeter 


220 


ELECTRICAL  PRINCIPLES  9 

or  size  of  the  plates  or  their  distance  apart.  But  if  the  nature  of  the 
plates  is  changed,  the  deflection  changes.  Thus,  while  copper  and 
zinc  in  dilute  sulphuric  acid  have  an  e.  m.  f.  of  one  volt,  carbon  and 
zinc  show  an  e.  m.  f.  of  at  least  L5  volts,  while  carbon  and  copper 
will  show  an  e.  m.  f.  of  very  much  less  than  a  volt.  Similarly,  by 
changing  the  nature  of  the  hquid  in  which  the  plates  are  immersed, 
we  can  produce  changes  in  the  deflection  of  the  voltmeter.  We 
learn,  therefore,  that  the  e.  m.  f.  of  a  galvanic  cell  depends  simply  up- 
on the  materials  of  which  the  cell  is  composed  and  not  at  all  upon  the 
shape,  size,  or  distance  apart  of  the  plates. 

Electrical  Resistance.  If  the  terminals  of  a  galvanic  cell  are 
connected  first  to,  say,  10  feet  of  No.  30  copper  wire,  and  then  to 
10  feet  of  No.  30  German-silver  wire,  it  is  found  that  a  compass 
needle  placed  at  a  given  distance  from  the  copper  wire  will  show  a 
much  larger  deflection  than  when  placed  the  same  distance  from  the 
German-silver  wire.  A  cell  therefore,  which  is  capable  of  develop- 
ing a  certain  fixed  electrical  pressure  is  able  to  force  very  much  more 
current  through  a  given  wire  of  copper  than  through  an  exactly  similar 
wire  of  German-silver.  We  say,  therefore,  that  German-silver  offers 
a  higher  resistance  to  the  passage  of  electricity  than  does  copper. 
Similarly,  every  particular  substance  has  its  own  characteristic 
power  of  transmitting  electrical  currents.  Silver  being  the  best  con- 
ductor of  any  known  substances,  the  resistances  of  different  sub- 
stances are  commonly  referred  to  silver  as  a  standard,  and  the  ratio 
between  the  resistance  of  a  given  wire  of  any  substance  and  the 
resistance  of  an  exactly  similar  silver  wire  is  called  the  specific  re- 
sistance of  that  substance.  The  specific  resistance  of  some  of  the 
commoner  metals  are  as  follows: 

Silver 1.00     Soft  iron 7.40     German  silver 20.4 

Copper 1.13     Nickel 7.87     Hard  steel 21.0 

Aluminum 2.00     Platinum 9.00     Mercury 62.7 

The  unit  of  resistance  is  the  resistance  of  0°  of  a  column  of  mer- 
cury 10G.3  centimeters  long  and  1  square  millimeter  in  cross-section. 
It  is  called  an  ohm,  in  honor  of  the  great  German  physicist,  Georg 
Ohm  (1789-1854).  A  length  of  9.35  feet  of  No.  30  copper  wire,  or  6.2 
inches  of  No.  30  German-silver  wire,  has  a  resistance  of  about  one 
ohm.  Copper  wire  of  the  size  shown  in  Fig.  10  has  a  resistance 
of  about  2.62  ohms  per  mile. 


221 


10  THE  MOTION  PICTURE 

The  resistances  of  all  metals  increase  with  rise  in  temperature. 
The  resistances  of  liquid  conductors,  on  the  other  hand,  usually 
decrease  with  rise  in  temperature.  Carbon 
and  a  few  other  solids  show  a  similar  be- 
^'^  ^"c^ppTr^wfre"^  '^°'  havior:  the  filament  in  an  incandescent  lamp 
has  only  about  half  the  resistance  when  hot 
that  it  has  when  cold.  The  resistances  of  wires  of  the  same  material 
are  found  to  be  directly  proportional  to  their  lengths,  and  inversely 
proportional  to  their  cross-sections. 

Ohm's  Law.  In  1827,  Ohm  announced  the  disco\cry  that 
the  currents  furnished  by  different  galvanic  cells,  or  combinations  of 
cells,  are  always  directly  proportional  to  the  e.  m.  f.'s  existing  in  the 
circuits  in  which  the  currents  flow,  and  inversely  proportional  to  the 
total  resistances  of  these  circuits;  that  is,  if  C  represents  the  current  in 
amperes,  E  the  e.  m.  f.  in  volts,  and  R  the  resistance  of  the  circuit  in 
ohms,  then  Ohm's  law  as  applied  to  the  complete  circuit  is 

E  electromotive  force 

C  =  — ;  i.  e.,  current  = ; 

R  resistance 

As  applied  to  any  portion  of  an  electrical  circuit,  Ohm's  law  is 

pd    .  potential  differeJice 

C=  — ;  /.  <?.,  current  = ^ '- 

^  resistance 

where  pd  represents  the  difference  of  potential  in  volts  between  any 

two  points  in  the  circuit,  and  r  the  resistance  in  ohms  of  the  conductor 

connecting  these  two  points.     This  is  one  of  the  most  important  laws 

in  physics. 

Both  of  the  above  statements  of  Ohm's  law  are  included  in  the 

equation 

ohms 

amperes  = 

volts 

Internal  Resistance  of  a  Galvanic  Cell.  If  the  zinc  and  copper 
plates  of  a  simple  cell  are  connected  to  an  ammeter,  and  the  distance 
between  the  plates  then  increased,  the  deflection  of  the  needle  is 
found  to  decrease,  or  if  the  amount  of  immersion  is  decreased  the 
current  also  will  decrease.  But  since  the  e.  m.  f.  of  a  cell  has  been 
.shown  to  be  wholly  independent  of  the  area  of  the  plates  immersed 


222 


ELECTRICAL  PRINCIPLES  11 

or  of  the  distance  between  them,  it  will  be  seen  from  Ohm's  law  that 
the  change  in  the  current  in  these  cases  must  be  due  to  some  change 
in  the  total  resistance  of  the  circuit.  Since  the  wire  which  consti- 
tutes the  outside  portion  of  the  circuit  has  remained  the  same,  we 
must  conclude  that  the  liquid  within  the  cell,  as  tvell  as  the  external 
wire,  offers  resistance  to  the  passage  of  the  current.  This  internal 
resistance  of  the  liquid  is  directly  proportional  to  the  distance  be- 
tween the  plates,  and  inversely  proportional  to  the  area  of  the  im- 
mersed portion  of  the  plates.  If,  then,  we  represent  the  external 
resistance  of  the  circuit  of  a  galvanic  cell  by  R^  and  the  internal  by 
Ri  then  Ohm's  law  as  applied  to  the  entire  circuit  takes  the  form 


Re+Ri 

Thus,  if  a  simple  cell  has  an  internal  resistance  of  2  ohms  and  an 
e.  m.  f.  of  1  volt,  the  current  which  will  flow  through  the  circuit 
when  its  terminals  are  connected  by  9.3  feet  of  No.  30  copper  wire 

(1  ohm)  is =    33  ampere.      This  is  about  the  current  which  is 

usually  obtained  from  an  ordinary  Daniell  cell. 

PRIMARY  CELLS 

Action  of  a  Simple  Cell.  If  the  simple  cell  already  mentioned 
— namely,  zinc  and  copper  strips  in  dilute  sulphuric  acid — is  care- 
fully observed,  it  will  be  seen  that,  so  long  as  the  plates  are  not  con- 
nected by  a  conductor,  fine  bubbles  of  gas  are  slowly  formed  at  the 
zinc  plate,  but  none  at  the  copper  plate.  As  soon,  however,  as  the 
two  strips  are  put  into  electrical  connection,  bubbles  instantly  ap- 
pear in  great  numbers  about  the  copper  plate  and  at  the  same  time  a 
current  manifests  itself  in  the  connecting  wire,  Fig.  11.  The  bub- 
bles are  of  hydrogen.  Their  original  appearance  on  the  zinc  plate 
may  be  prevented  either  by  using  a  plate  of  chemically  pure  zinc,  or 
by  amalgamating  impure  zinc,  that  is,  by  coating  it  over  with  a  thin 
film  of  mercury.  But  the  bubbles  on  the  copper  cannot  be  thus  dis- 
posed of.  They  are  an  invariable  accompaniment  of  the  current  in 
the  circuit.  If  the  current  is  allowed  to  run  for  a  considerable  time, 
it  will  be  found  that  the  zinc  wastes  away,  even  though  it  has  been 
amalgamated,  but  the  copper  plate  does  not  undergo  any  change. 


223 


12 


THE  MOTION  PICTURE 


-h 


0) 

-_Z^ 

-J 

1    <1^ 

-  r^ 

— ^ 

-b-p. 

r(U^ 

r_^ 

-.  ■r^^=-^^  i  =" 

-u); 

■~ 

0  r 

■1 

-~ 

^2^ 

-  (I)" 

_ir 

-    '— I^^  "L"  0   1 

-S  0 

^d 

r-: 

-^- -"-^  r 

to.— -::d| 

An  electrical  current  in  a  simple  cell  is,  then,  accompanied  by 
the  eating  up  of  the  zinc  plate  by  the  hquid,  and  by  the  evolution  of 
hydrogen  bubbles  at  the  copper  plate.  In  every  type  of  galvanic 
cell,  actions  similar  to  these  two  are  always  found,  that  is,  one  of  the 
plates  is  always  eaten  up,  and  on  the  other 
some  element  is  deposited.  The  plate  which 
is  eaten  is  always  the  one  which  is  found 
to  be  negatively  charged,  while  the  other 
is  always  found  to  be  positively  charged; 
so  that  in  all  galvanic  cells,  when  the  ter- 
minals are  connected  through  a  ware,  the 
positive  electricity  flows  through  this  wire 
from  the  uneaten  plate  to  the  eaten  plate. 
It  will  be  remembered  that  the  direction  in 
which  the  positive  electricity  flows  is  taken  for 
convenience  as  the  direction  of  the  current. 

Theory  of  Action  of  a  Simple  Cell.  X 
simple  cell  may  be  made  of  any  two  dissimilar 
metals  immersed  in  a  solution  of  any  acid  or 
salt.  For  simplicity,  let  us  examine  the  action 
of  a  cell  composed  of  plates  of  zinc  and  copper  immersed  in  a  dilute 
solution  of  hydrochloric  acid.  The  chemical  formula  for  hydrochloric 
acid  is  IICl.  This  means  that  each  molecule  of  the  acid  consists  of  one 
atom  of  hydrogen  comliined  with  one  atom  of  chlorine.  In  accordance 
with  the  theory  now  in  vogue  among  physicists  and  chemists,  when 
hydrochloric  acid  is  mixed  with  water  so  as  to  form  a  dilute  solution, 
the  IICl  molecules  split  up  into  two  electrically  charged  parts,  called 
ions,  the  hydrogen  ion  carrying  a  positive  charge  and  the  chlorine 
ion  an  ecjual  negative  charge.  Fig.  12.  This  phenomenon  is  known 
as  dissociation.  The  solution  as  a  whole  is  neutral,  /.  c.,  it  is  un- 
charged, because  it  contains  just  as  many  positive  as  negative  ions. 

^^^^en  a  zinc  plate  is  placed  in  such  a  solution,  the  acid  attacks 
it  and  pulls  zinc  atoms  into  solution.  Now,  whenever  a  metal  dis- 
solves in  an  acid,  its  atoms,  for  some  unknowTi  reason,  go  into  solu- 
tion bearing  little  positive  charges.  The  corresponding  negative 
charges  mvst  he  left  on  the  zinc  plate  in  precisely  the  same  way  in 
which  a  negative  charge  is  left  fm  silk  when  positive  electrification 
is  produced  on  a  glass  rod  by  rubbing  it  with  the  silk.     It  is  in  this 


Fig.   11.     Action  of  a 
Simple  Cell 


224 


ELECTRICAL  PRINCIPLES 


13 


H- 


Cu 


+ 


-®- 


& 


,__n-  -CI  -  M  E:r:zn-:Ur-::l 


Zn 


way,  then,  that  we  attempt  to  account  for  the  negative  charge  which 
we  find  upon  the  zinc  plate  in  the  experiment  ilhistrated  in  Fig.  4. 

The  passage  of  positively  charged  zinc  ions  into  solution  gives 
a  positive  charge  to  the  solution  about  the  zinc  plate,  so  that  the 
hydrogen  ions  tend  to  be  repelled  toward  the  copper  plate.  \^Tien 
these  repelled  hydrogen  ions  reach  the  copper  plate  some  of  them 
give  up  their  charges  to  it  and  then  collect  as  bubbles  of  hydrogen 
gas.  It  is  in  this  way  that  we  account  for  the  positive  charge  which 
we  find  on  the  copper  plate  in  the  experiment  illustrated  in  Fig.  4. 

If  the  zinc  and  copper  plates  are  not  connected  by  an  outside 
conductor,  this  passage  of  positively  charged  zinc  ions  into  solution 
continues  but  a  very  short  time,  for  the  zinc  soon  becomes  so  strongly 
charged  negatively  that  it  pulls  back  on  the  plus  zinc  ions  with  as  much 
force  as  the  acid  pulls  them  into 
solution.  In  precisely  the  same 
way  the  copper  plate  soon  ceases 
to  take  up  any  more  positive  elec- 
tricity from  the  hydrogen  ions, 
since  it  soon  acquires  a  large  enough 
plus  charge  to  repel  them  from  it- 
self with  a  force  equal  to  that  with 
which  they  are  being  driven  out  of 
solution  by  the  positively  charged 
zinc  ions.  It  is  in  this  way  that  we 
account  for  the  fact  that  on  open 
circuit  no  chemical  action  goes  on 
in  the  simple  galvanic  cell,  the  zinc  and  copper  plates  simply  becom- 
ing charged  to  a  definite  difference  of  potential  which  is  called  the 
e.  m.  f.  of  the  cell. 

When,  however,  the  copper  and  zinc  plates  are  connected  by  a 
wire,  a  current  at  once  flows  from  the  copper  to  the  zinc,  and  the 
plates  thus  begin  to  lose  their  charges.  This  allows  the  acid  to  pull 
more  zinc  into  solution  at  the  zinc  plate,  and  allows  more  hydrogen 
to  go  out  of  solution  at  the  copper  plate.  These  processes,  therefore, 
go  on  continuously  so  long  as  the  plates  are  connected.  Hence,  a 
continuous  current  flows  through  the  connecting  wire  until  the  zinc 
is  all  eaten  up  or  the  hydrogen  ions  have  all  been  driven  out  of  the 
solution,  i.  e.,  until  either  the  plate  or  the  acid  has  become  exhausted. 


Fig.  12. 


Di.ssooiation  of  Ions  in 
Simple  Cell 


225 


14 


THE  MOTION  PICTURE 


Polarization.  If  the  simple  cell,  which  has  been  described, 
is  connected  to  an  ammeter  and  the  deflection  observed  for  a  few 
minntes,  it  is  found  to  produce  a  current  of  continually  decreasing 
strength;  but  if  the  hydrogen  is  removed  from  the  copper  plate  by 
taking  out  the  plate  and  drying  it,  the  deflection  returns  to  its  first 
value.     This  phenomenon  is  called  polarization. 

The  presence  of  the  hydrogen  on  the  positive  plate  causes  a 
diminution  in  the  strength  of  the  current  for  two  reasons:  First,  since 
hydrogen  is  a  non-conductor,  by  collecting  on 
the  plate  it  diminishes  the  effective  area  of  the 
plate  and,  therefore,  increases  the  internal 
resistance  of  the  cell ;  second,  by  collecting  upon 
the  copper  plate  it  lowers  the  e.  m.  f.  of  the 
cell,  because  it  virtually  substitutes  a  hydrogen 
plate  for  the  copper  plate,  and  we  have  already 
seen  that  a  change  in  any  of  the  materials  of 
which  a  cell  is  composed  changes  its  e.  m.  f. 

The  different  forms  of  galvanic  cells  in 
common  use  differ  chiefly  in  different  devices 
employed  either  for  disposing  of  the  hydrogen 
bubbles  or  for  preventing  their  formation. 
The  most  common  tj-pes  of  such  cells  are 
described  in  the  following  sections. 

Bichromatic  Cell.  The  bichromate  cell, 
Fig.  13,  consists  of  a  plate  of  zinc  immersed 
in  sulphuric  acid  between  two  plates  of  carbon, 
carljon  being  used  instead  of  copper  because  it  gives  a  greater  e.  m.  f. 
In  the  sulphuric  acid  is  dissolved  some  bichromate  of  potassium  or 
sodium,  the  function  of  which  is  to  unite  chemically  with  the  hydro- 
gen as  fast  as  it  is  formed  at  the  positive  plate,  thus  preventing  its 
accumulation  upon  this  plate.*  Such  a  cell  has  the  high  e.  m.  f. 
of  2.1  volts.  Its  internal  resistance  is  low — from  .2  to  .5  ohm — since 
the  plates  are  generally  large  and  close  together.  It  will  be  seen, 
therefore,  that  when  the  external  resistance  is  very  small  it  is  capable 
of  furnishing  a  current  of  from  5  to  10  amperes.  Since,  however,  the 
chromic  acid  formed  by  the  union  of  the  sulphuric  acid  with  the  bi- 


Fig.    12 


Bichromate  Cell 


*To  set  up  a  bichromate  cell,  dissolve  1  2  parts,  l)y  weitrht,  of  soditim  liiehromate  in 
180  parts  of  IjoiliriK  water.      After coolinii,  adil  2'>  parts  of  conimerfial  suli)luiric  acid. 


226 


ELECTRICAL  PRINCIPLES 


15 


chromate  attacks  the  zinc  even  when  the  circuit  is  open,  it  is  neces- 
sary to  lift  the  zinc  from  the  hcjiiid  by  the  rod  A,  when  the  cell  is  not 
in  use.  Such  cells  are  useful  where  large  currents  are  needed  for  a 
short  time.  The  great  disadvantages  are  that  the  fluid  deteriorates 
rapidly,  and  that  the  zinc  cannot  be  left  in  the  liquid. 

Danicll  Cell.  The  Daniell  cell  consists  of  a  zinc  plate  immersed 
in  zinc  sulphate,  and  a  copper  plate  immersed  in  copper  sulphate, 
the  two  liquids  being  kept  apart  either  by  means  of  a  porous  earthen 
cup,  as  in  the  types  shown  in  Fig.  14,  or  else  by  gravity,  as  in  the  type 
shown  in  Fig.  15.     This  last  type,  commonly  called  the  gravity,  or 


% 

O 

o  o9 

ziOCfG 


Fig.   14.     Section  of  Daniell  Cell  Danio'l  Cell  (Commercial  Type) 

croicfoot  type,  is  used  almost  exclusively  on  telegraph  lines.  The 
copper  sulphate,  being  the  heavier  of  the  two  liquids,  remains  at  the 
bottom  about  the  cop])er  plate,  while  the  zinc  sulphate  remains  at  the 
top  about  the  zinc  plate. 

In  this  cell  polarization  is  almost  entirely  avoided,  for  the  reason 
that  no  opportunity  is  given  for  the  formation  of  hydrogen  bubbles. 
For,  just  as  the  hydrochloric  acid  solution  consists  of  positive  hydro- 
gen ions  and  negative  chloride  ions  in  water,  so  the  zinc  sulphate 
(ZnSO^)  solution  consists  of  positive  zinc  ions  and  negative  SO^ 
ions.  Now  the  zinc  of  the  zinc  plate  goes  into  solution  in  the  zinc 
sulphate  in  precisely  the  same  way  that  it  goes  into  solution  in  the 


227 


16 


THE  MOTION  PICTURE 


hydrochloric  acid  of  the  simple  cell.  This  gives  a  positive  charge 
to  the  solution  about  the  zinc  plate,  and  causes  a  movement  of  the 
positive  ions  between  the  two  plates  from  the  zinc  toward  the  copper, 
and  of  negative  ions  in  the  opposite  direction,  both  the  Zn  and  the 
SO^  ions  being  able  to  pass  through  the  porous  cup.  Since  the  posi- 
tive ions  about  the  copper  plate  consist  of  atoms  of  copper,  it  will  be 
seen  that  the  material  which  is  driven  out  of  solution  at  the  copper 
plate,  instead  of  being  hydrogen,  as  in  the  simple  cell,  is  metallic 
copper.  Since,  then,  the  element  which  is  deposited  on  the  copper 
plate  is  of  the  same  molecvilar  structure  as  that  of  which  it  already 
consists,  it  is  clear  that  neither  the  electromotive  force  nor  the 
resistance  of  the  cell  can  be  changed  by  the  presence  of  this 
deposit,  i.  e.,  the  cause  of  the  polarization  of  the  simple  cell  has 
been  removed. 

The  great  advantage  of  the  Daniell  cell  lies  in  the  relatively 
high  degree  of  constancy  in  its  e.  m.  f.  (1.08  volts).  It  has  a  com- 
paratively high  internal  resistance — one  to  six 
ohms — =and  is,  therefore,  incapable  of  produc- 
ing very  large  currents,  about  one  ampere  at 
most.  It  will  furnish  a  very  constant  cur- 
rent, however,  for  a  great  length  of  time;  in 
fact  until  all  of  the  copper  is  driven  out  of 
the  copper  sulphate  solution.  In  order  to 
keep  a  constant  supply  of  the  copper  ions  in 
the  solution,  copper  sulphate  crystals  are  kept 
in  the  compartment  »S  of  the  cell  of  Fig.  14, 
or  in  the  bottom  of  the  gravity  cell.  These 
dissolve  as  fast  as  the  solution  loses  its 
strength  through  the  deposition  of  copper  on 
the  copper  plate. 

The  Daniell  is  a  so-called  closed-circuit  cell, 
i.  c,  its  circuit  should  be  left  closed — through  a  resistance  of  thirty 
or  forty  ohms — whenever  the  cell  is  not  in  use.  If  it  is  left  on  open 
circuit,  the  copper  sulphate  diffuses  through  the  porous  cup,  and  a 
brownish  muddy  deposit  of  copper  or  copper  oxide  is  formed  upon 
the  zinc.  Pure  copper  is  also  deposited  in  the  pores  of  the  porous 
cu|).  Both  of  these  actions  damage  the  cell.  \Mien  the  circuit  is 
cl.)sed,  however,  since  the  electrical  forces  always  keep  the   copper 


Fig.   15.     Gravity  Cell 


228 


ELECTRICAL  PRINCIPLES 


17 


Leclanche  Cell 


ions  moving  toward  the  copper  plate,  these  damaging  effects  are  to  a 
large  extent  avoided 

Leclanche  Cell,  The  Leclanche  cell,  Fig.  16,  consists  of  a  zinc 
rod  in  a  solution  of  ammonium  chloride — 150  g.  to  a  liter  of  water — 
and  a  carbon  plate  placed  inside  of  a  porous  cup  which  is  packed 
full  of  manganese  dioxide  and  powdered  graphite  or  carbon.  As 
in  the  simple  cell,  the  zinc  dissolves  in  the  liquid,  and  hydrogen  is 
liberated  at  the  carbon,  or  positive,  plate.  Here 
it  is  slowly  attacked  by  the  manganese  dioxide. 
This  chemical  action  is,  however,  not  quick 
enough  to  prevent  rapid  polarization  when 
large  currents  are  taken  from  the  cell.  The 
cell  slowly  recovers  when  allowed  to  stand  for 
a  while  on  open  circuit.  The  e.  m.  f.  of  a 
Leclanche  cell  is  about  1.5  volts,  and  its  initial 
internal  resistance  is  somewhat  less  than  an 
ohm;  It,  therefore,  furnishes  a  momentary 
current  of  from  one  to  three  amperes. 

The  immense  advantage  of  this  type  of 
cell  lies  in  the  fact  that  the  zinc  is  not  at  all  eaten  by  the  ammonium 
chloride  when  the  circuit  is  open,  and  that,  therefore,  unlike  the 
Daniell  or  bichromate  cells,  it  can  be  left  for  an  indefinite  time 
on  open  circuit  without  deterioration.  Leclanche  cells  are  used 
almost  exclusively  where  momentary  currents  only  are  needed,  as, 
for  example,  on  door-bell  circuits.  The  cell  requires  no  attention 
for  years  at  a  time,  other  than  the  occasional  addition  of  water  to 
replace  loss  by  evaporation,  and  the  occasional  addition  of  ammo- 
nium chloride  (NH^Cl)  to  keep  positive  NH^  and  negative  CI  ions  in 
the  solution. 

Dry  Cell.  The  dry  cell  is  only  a  modified  form  of  the  liCclanche 
cell.  It  is  not  really  dry,  since  the  zinc  and  carbon  plates  are  im- 
bedded in  moist  paste  which  consists  usually  of  one  part  of  crystals 
of  ammonium  chloride,  three  parts  of  plaster  of  Paris,  one  part  of 
zinc  oxide,  one  part  of  zinc  chloride,  and  two  parts  of  water.  The 
plaster  of  Paris  is  necessary  in  order  to  give  the  paste  the  re- 
quired rigidity.  As  in  the  Leclanche  cell,  the  current  is  produced 
by  the  chemical  action  of  the  ammonium  chloride  upon  the  zinc 
plate  which  forms  the  outside  wall  of  the  cell. 


229 


18 


THE  MOTION  PICTURE 


Combinations  of  Cells.  There  are  two  ways  in  which  cells 
may  be  combined:  First,  in  series;  and  second,  in  parallel.  When 
they  are  connected  in  series  the  zinc  of  one  cell  is  joined  to  the  copper 
of  the  second,  the  zinc  of  the  second  to  the  copper  of  the  third,  etc., 
the  copper  of  the  first  and  the  zinc  of  the  last  being  joined  to  the  ends 
of  the  external  resistance,  Fig.  17.  The  e.  m.  f.  of  such  a  combina- 
tion is  the  sum  of  the  e.  m.  f.'s  of  the  single  cells.  The  internal  re- 
sistance of  the  combination  is  also  the  sum  of  the  internal  resistances 
of  the  single  cells.  Hence,  if  the  external  resistances  are  very  small, 
the  current  furnished  by  the  combination  will  not  be  larger  than  that 
furnished  by  a  single  cell,  since  the  total  resistance  of  the  circuit  has 
been  increased  in  the  same  ratio  as  the  total  e.  m.  f.     But  if  the  ex- 


/Tnr2Rr\       /iymr\ 


TC^^Z^- 


lcj----: 


"ci^^^ 


Fig.  17.     Cells  Connected  ki  Series 

ternal  resistance  is  large,  the  current  produced  by  the  combination 
will  be  very  much  greater  than  that  pn^duced  by  a  single  cell.  Just 
how  much  greater  can  always  be  determined  by  applying  Ohm's  law, 
for  if  there  are  n  cells  in  series,  and  E  is  the  e.  m.  f.  of  each  cell,  the 
total  e.  ra.  f.  of  the  circuit  is  n  E.  Hence  if  Re  is  the  external  resist- 
ance and  Ri  the  internal  resistance  of  a  single  cell,  then  Ohm's  law 
gives 

nE 
'      C  = 


Re  +    tfRi 


If  the  ?/  cells  are  connected  in  parallel,  that  is,  if  all  the  coppers 
are  connected  together  ant!  all  the  zincs,  as  in  Fig.  18,  the  e.  m.  f.  of 
the  combination  is  only  the  e.  m.  f.  of  a  single  cell,  while  the  internal 

.1 
resistance  is  —  of  that  of  a  single  cell,  since  connecting  the  cells  in 


230 


ELECTRICAL  PRINCIPLES 


19 


this  way  is  simply  equivalent  to  multiplying  the  area  of  the  plates  n 
times.  The  current  furnished  by  such  a  combination  will  be  given 
by  the  formula 

E 

C  =  - 


/?.  + 


R^ 


If,  therefore,  Rg  is  negligibly  small,  as  in  the  case  of  a  heavy 
copper  wire,  the  current  flowing  through  it  will  be  n  times  as  great  as 
that  which  couid  be  made  to  flow  through  it  by  a 
single  cell.      These  considerations  show  that  the 
niles  which  should  govern  the  combination  of  cells 
are  as  follows: 

When  the  external  resistance  is  large  in  com- 
pnrison  with  the  internal  resistance  of  a  single  cell, 
the  cells  should  be  connected  in  series. 

When  the  external  resistance  is  small  in  com- 
parison with  the  internal  resistance  of  a  single  cell, 
the  cells  should  he  connected  in  parallel. 

Storage  Battery.  If  two  lead  plates  are 
immersed  in  sulphuric  acid  and  the  current  sent 
through  the  cell,  the  anode  or  plate  at  which 
the  current  enters  the  solution  will  be  foinid 
in  the  course  of  a  few  minutes  to  turn  dark 
brown.  This  brown  coat  is  a  compound  of 
lead  with  the  oxygen  which,  in  the  case  of  the  platinum  electrodes, 
was  evolved  as  a  gas.  The  other  lead  plate  is  not  affected  by  the 
hydrogen,  which  is,  in  this  case,  as  in  that  of  the  platinum,  evolved  as 
a  gas.  Since  the  passage  of  the  current  through  this  cell  has  left 
one  plate  unchanged,  while  it  has  changed  the  surface  of  the  other 
plate  to  a  new  substance,  namely,  lead  peroxide,  PbO,,  it  might  be 
expected  that  if  the  charging  battery  were  removed,  and  these  two 
dissimilar  plates  connected  with  a  wire,  a  current  will  flow  through 
the  wire,  for  the  arrangement  is  now  essentially  a  simple  galvanic 
cell,  which  in  its  essentials  consists  simply  of  two  dissimilar  plates 
immersed  in  an  electrolyte^a  conducting  liquid  other  than  a  molten 
metal.  In  this  case  the  plate  ha\nng  the  lead  peroxide  upon  it  cor- 
responds to  the  copper  of  an  ordinary  cell,  and  the  unchanged  lead 


Fig.   IS.     Cells  Con- 
nected in  Parallel 


231 


20 


THE  MOTION  PICTURE 


plate  to  the  zinc.  The  arrangement  will  furnish  a  current  until  the 
lead  peroxide  is  all  used  up.  The  only  important  difference  between 
a  commercial  storage  cell  and  the  two  lead  plates  just  considered,  is 
that  the  former  is  provided  in  the  process  of 
manufacture  with  a  very  much  thicker  coat  of 
the  active  material — lead  peroxide  on  the  posi- 
tive plate,  and  a  porous,  spongy  lead  on  the 
negative — than  can  be  formed  by  a  single 
charging  such  as  we  considered.  In  one  tyY>e 
of  storage  cell  this  active  material  is  actually 
formed  by  the  repeated  charging  and  discharg- 
ing of  plates  which  are  originally  ordinary 
sheets  of  lead.  With  each  new  charging  a 
slightly  thicker  layer  of  the  lead  peroxide  is 
formed.  In  the  more  common  type  of  commer- 
cial cell  the  active  material  is  pressed  into 
interstices  of  the  plate  in  the  form  of  a  paste. 
It  will  be  seen  from  this  discussion  that  a  storage 
battery  is  not,  properly  speaking,  a  device  for 
storing  electricity.  It  is  rather  a  device  in  which  the  electrical  cur- 
rent produces  chemical  changes,  and  these  new  chemicals,  so  long  as 
they  last,  are  capable  of  generating  a  new  electrical  current. 


19.     Magnetic  Prop- 
erties of  a  Loop 


ELECTROMAGNETISAl 

Magnetic  Properties  of  a  Loop.     We  have  seen  that  an  elec- 
trical current  is  surrounded  by  a  magnetic  field  the  direction  of  which 

is  given  by  the  right-hand  rule.  We  have 
seen  also  that  a  loop  or  coil  of  wire 
through  which  a  current  flows  produces  a 
magnetic  field  of  the  shape  shown  in  Fig. 
7.  Now,  if  such  a  loop  is  suspended  in 
the  manner  shown  in  Fig.  19  while  a 
current  is  passed  through  it,  it  is  found 
to  slowly  set  itself  in  an  east-and-west 
plane,  and  so  that  the  face  of  the  loop  from 
which  the  magnetic  lines  emerge,  Fig.  20, 
is  toward  the  north.  In  other  words,  the 
loop  will  be  found  to  behave  with  respect 


Fig    20. 


Macnptic  Properties 
of  a  Loop 


232 


ELECTRICAL  PRINCIPLES 


21 


to  the  earth  or  to  any  other  magnet  precisely  as  though  it  were  a 
flat  magnetic  disk  whose  boundary  is  the  wire,  the  face  which  turns 
toward  the  north,  that  is,  that  from  which  the  magnetic  hues  emerge, 
being  an  N  pole  and  the  other  an  S  pole. 

Magnetic  Properties  of  a  Helix.     If  a  wire  carrying  a  current  be 
wound  in  the  form  of  a  helix  and  held  near  a  suspended  magnet 


Fig.  21.     Magnetic  Properties  of  a  Helix 

as  in  Fig.  21,  the  coil  will  be  found  to  act  in  every  respect  like  a  mag- 
net, with  an  N  pole  at  one  end  and  an  S  pole  at  the  other. 

This  result  might  have  been  predicted  from  the  fact  that  a  single 
loop  is  equivalent  to  a  flat-disk  magnet.  For  when  a  series  of  such 
disks  is  placed  side  by  side,  as  in  the  helix,  the  result  must  be  the 

z'''' r~~--.  Direction 

Fig.  22.     Magnetic  Field  Fig.  23.     Right-Hand  Rule  for  a  Helix 

About  a  Helix 

same  as  placing  a  series  of  disk  magnets  in  a  row,  the  N  pole  of  one 
being  directly  in  contact  with  the  S  pole  of  the  next,  etc.  These  poles 
would,  therefore,  all  neutralize  each  other  except  at  the  two  ends.  We, 
therefore,  get  a  magnetic  field  of  the  shape  shown  in  Fig.  22,  the 
direction  of  the  arrows  representing  as  usual  the  direction  in  which 
an  N  pole  tends  to  move. 

Rules  for  North  and  South  Poles  of  a  Helix.    The  right-hand 


233 


22 


THE  MOTION  PICTURE 


Fig.  24.     A  Simple  Electro- 
magnet and  Its  Field 


nile  as  already  given  is  sufficient  in  every  case  to  determine  which 
is  the  N  and  which  the  S  pole  of  a  helix,  i.  e.,  from  which  end  the 

lines  of  magnetic  force  emerge  from  the 
helix  and  at  w^hich  end  they  enter  it.  But 
it  is  found  convenient,  in  the  consideration 
of  coils,  to  restate  the  right-hand  rule  in  a 
slightly  different  way,  Fig.  23,  thus: 

If  the  coil  is  grasped  in  the  right  hand 
in  such  a  umy  that  the  fingers  point  in  the 
direction  in  which  the  current  is  flowing  in 
the  wires,  the  thumh  will  point  in  the  direction  of  the  north  pole  of  the 
helix. 

Similarly,  if  the  sign  of  the  poles  is  kno\\Ti,  but  the  direction  of 
the  current  unknown,  the  latter  may  be  determined  as  follows: 

If  the  right  hand  is  placed  against  the  coil  ivith  the  thumb  pointing 
in  the  direction  of  the  lines  of  force,  i.  e.,  toward  the  north  pole  of  the 
helix,  the  fingers  will  pass  around  the  coil  in  the  direction  in  which 
the  current  is  flowing. 

Electromagnet.     If  a  core  of  soft  iron  be  inserted  in  the  helix, 
Fig.  24,  the  poles  will  be  found  to  be  enormously  stronger  than  before. 
This  is  because  the  core  is  magnet- 
ized by  induction  from  the  field  of  ■ — "^^^ "^^^^^ 


'Mill 

y  111 
ii  111 
ii  III 

II  In 

Mill 

ll  I  lll 

111''!' 
i'  I" 

111!'" 


v^ 


111  II 
III  II 

"'1' 
Hill 

till  1 

1111  1 

HM    l| 


h  I  II 
h  I  'i 
II    II    I 


Fig.  25.     Horseshoe  Electromagnet 
with  Armature 


Fig.  26.     Field  of  Horseshoe 
Electromagnet 


the  helix  in  precisely  the  same  way  in  which  it  would  be  magnetized 
by  induction  if  placed  in  the  field  of  a  permanent  magnet.  The  new 
field  strength  about  the  coil  is  now  the  sum  of  the  fields  due  to  the 
core  and  that  due  to  the  coil.  If  the  current  is  broken,  the  core  will  at 
once  lose  the  greater  part  of  its  magnetism.     If  the  current  is  re- 


234 


SCENE  FROM  "POEMS  IN  PICTURES,"  BY  GAUMONT  ^    ^     ^        ^ 

A  Series  of  Imaginative  Conceptions  Which  Deeply  Impressed  ^he^^^^^^^  Element  of  the  Country 

Courtesy  of  the  Kleine  Optical  Co.,  Ltiicago 


ELECTRICAL  PRINCIPLES 


23 


versed,  the  polarity  of  the  core  will  be  reversed.     Such  a  coil  with  a 
soft-iron  core  is  called  an  electromagnet. 

The  strength  of  an  electromagnet  can  be  very  greatly  increased 
by  giving  it  such  form  that  the  magnetic  lines  can  remain  in  iron 
throughout  their  entire  length  instead  of  emerging  into  air,  as  they 
do  in  Fig.  24.  For  this  reason  electromagnets  are  usually  built  in 
the  horseshoe  form  and  provided  with  an  armature  A,  Fig.  25, 
through  which  a  complete  iron  path  for  the  lines  of  force  is  estab- 
lished as  shown  in  Fig.  2G.    The  strength  of  such  a  magnet  depends 


Fig.   27.     Simple  Electric  Bell  and  Connections 

chiefly  upon  the  number  of  ampere-turns  which  encircle  it,  the  ex- 
pression ampere-turns  denoting  the  product  of  the  number  of  turns  of 
wire  about  the  magnet  by  the  number  of  amperes  flowing  in  each 
turn.  Thus  a  current  of  y^  ampere  flowing  1,000  times  around 
a  core  will  make  an  electromagnet  of  precisely  the  same  strength  as 
a  current  of  1  ampere  flowing  10  times  about  the  core. 

Electric  Bell.  The  electric  bell,  Fig.  27,  is  one  of  the  simplest 
applications  of  the  electromagnet.  Wlien  the  button  P  is  pressed,  the 
electric  circuit  of  the  battery  is  closed  and  a  current  flows  in  at  A, 
through  the  magnet,  over  the  closed  contact  C,  and  out  again  at  B. 
Rut  no  sooner  is  this  current  established  than  the  electromagnet  E 
pulls  over  the  armature  a,  and  in  so  doing  breaks  the  contact  at  C. 


k 


235 


24  THE  MOTION  PICTURE 

This  stops  the  current  and  demagnetizes  the  magnet  E.  The  arm- 
ature is  then  thrown  back  against  C  by  the  elasticity  of  the  spring  s 
which  supports  it.  No  sooner  is  the  contact  made  at  C  than  the 
current  again  begins  to  flow  and  the  former  operation  is  repeated. 
Thus  the  circuit  is  automatically  made  and  broken  at  C  and  the 
hammer  H  is,  in  consequence,  set  into  rapid  vibration  against  the 
rim  of  the  bell. 

LAWS  OF  CURRENT  FLOW 

RESISTANCE 

All  substances  resist  the  passage  of  electricity,  but  the  resist- 
ance offered  by  some  is  very  much  greater  than  that  offered  by 
others.  Metals  have  by  far  the  least  resistance  and,  of  these,  silver 
possesses  the  least  of  any.  In  other  words,  silver  is  the  best  conduc- 
tor. If  the  temperature  remains  the  same,  the  resistance  of  a  conduc- 
tor is  not  affected  by  the  current  passing  through  it.  A  current  of 
ten,  twenty,  or  any  number  of  amperes  may  pass  through  a  circuit, 
but  its  resistance  will  l)e  unchanged  with  constant  temperature.  Re- 
sistance is  affected  by  the  temperature  and  also  by  the  degree  of 
hardness.     Annealing  decreases  the  resistance  of  a  metal. 

Conductance.  Conductance  is  the  inverse  of  resistance,  that  is, 
if  a  conductor  has  a  resistance  of  R  ohms,  its  conductance  is  equal 

to  A. 
R 

Resistance  Proportional  to  Length.  The  resistance  of  a  con- 
ductor is  directly  proportional  to  its  length.  Hence,  if  the  length  of 
a  conductor  is  douliled,  the  resistance  is  doubled,  or  if  the  length  is 
divided,  say  into  three  equal  parts,  then  the  resistance  of  each  part 
is  one-thin!  the  total  resistance. 

Example.  The  resistance  of  1,28.3  feet  of  a  certain  wire  is  6.9  ohms. 
What  is  the  resistance  of  1 42  feet  of  the  same  wire? 

Soliitinn.     As  the  resistance  is  directly  proportional  to  the  length  we 

have  the  proportion 

required  reaifttnnce  :  6.9  :  :  112  :  1283 

required  resistance  142 

or,  =  

6.9  1283 

142 

Hence,  required  resistance  =  6.9  X 

1283 

=  .76  ohm  (approx.) 

Ans.  .76  ohm. 


236 


ELECTRICAL  PRINCIPLES  25 

Example.  The  resistance  of  a  wire  having  a  length  of  521  feet  is  .11 
ohm.    What  length  of  the  same  wire  will  have  a  resistance  of  .18  ohm? 

Solution.  As  the  resistance  is  proportional  to  length,  we  have  the  pro- 
portion 

required  length  :  521::. 18:. 11 

required  length         .18 

or,  =   

521  .11 

.     ,  ,        ,  -18 

Hence,  required  length    =   521  X  — 

=  852  feet  (approx.) 

Ans.  852  feet. 

Resistance  Inversely  Proportional  to  Cross=Section.  The  re- 
sistance of  a  conductor  is  inversely  proportional  to  its  cross-sec- 
tional area.  Hence  the  greater  the  cross-section  of  a  wire  the  less 
is  its  resistance.  Therefore,  if  two  wires  have  the  same  length, 
but  one  has  a  cross-section  three  times  that  of  the  other,  the  resist- 
ance of  the  former  is  one-third  that  of  the  latter. 

Example.     The  ratio  of  the  cross-sectional  area  of  one  wire  to  that  of 

257 
another  of  the  same  length  and  material  is —  •    The  resistance  of  the  former 

101 

is  16.3  ohms.    What  is  the  resistance  of  the  latter? 

Solution.  As  the  resistances  are  inversely  proportional  to  the  cross- 
sections,  the  smaller  wire  has  the  greater  resistance,  and  we  have  the  proportion 

required  resistance  :  10. 3  :  :  257  :  101 

required  resistance       257 

or, '■ =  — 

16.3  101 

257 

Hence,  required  resistance  =  10.3  X  — 

^  101 

=  41.5  ohms  (approx.) 

Ans.  41.5  ohms 

Example.  If  the  resistance  of  a  wire  of  a  certain  length  and  having  a 
cross-sectional  area  of  .0083  square  inch  is  1.7  ohms,  what  would  be  its  resist- 
ance if  the  area  of  its  cross-section  were  .092  square  inch? 

Solution.  Since  increasing  the  cross-sectional  area  of  a  wire  decreases 
its  resistance,  we  have  the  proportion 

required  resistance  :  1.7  :  :  .0083  :  .092 

required  resistance  .0083 


or, 

1.7  .092 

.0083 
Hence,  required  resistance  =  1.7  X 


.092 
=  .15  ohm  (approx.) 

Ans.  .15  ohm. 


237 


26  THE  MOTION  PICTURE 

As  the  area  of  a  circle  is  proportional  to  the  square  of  its  diam- 
eter, it  follows  that  the  resistance  of  round  conductors  are  inversely 
proportional  to  the  squares  of  their  diameters. 

Example.  The  resistance  of  a  certain  wire  having  a  diameter  of  .1 
inch  is  12.6  ohms.  What  would  be  its  resistance  if  the  diameter  were  increased 
to   .32   inch? 

Solution.  The  resistances  being  inverselj'  proportional  to  the  squares 
of  the  diameters,   we  have 

required  resistance  :  12. G  :  :  .1^  :  .32^ 

required  resistance         .1^ 

or,  =  — k 

12.6  .32^ 

.1^ 
Hence,  required  resistance  =  12.6  X  — -„ 

.32^ 

12.6  X  .01 


.1024 
=  1.23  ohms  (approx.) 

Ans.  1.23  ohms. 

Specific  Resistance.  The  specific  resistance  of  a  substance 
is  the  resistance  of  a  portion  of  that  substance  of  unit  length  and 
unit  cross-section  at  a  standard  temperature.  The  units  commonly 
used  are  the  centimeter  of  the  inch,  and  the  temperature  that  of 
melting  ice.  The  specific  resistance  may  therefore  be  said  to  be 
the  resistance  (usually  stated  in  microhms)  of  a  centimeter  cube  or 
of  an  inch  cube  at  the  temperature  of  melting  ice.  If  the  specific 
resistances  of  two  substances  are  known,  then  their  relative  resistance 
is  given  by  the  ratio  of  the  specific  resistances. 

Conductivity.  Conductivity  is  the  reciprocal  of  specific  resist- 
ance. 

Example.  A  certain  copper  wire  at  the  temperature  of  melting  ice 
has  a  resistance  of  29.7  ohms.  Its  specific  resistance — resistance  of  1  centi- 
meter cube  in  microhms — is  1.594,  and  that  of  platinum  is  9.032.  What  would 
be  the  resistance  of  a  platinum  wire  of  the  same  size  and  length  of  the  copper 
wire,  and  at  the  same  temperature? 

Solution.  The  resistance  would  be  in  direct  ratio  of  the  specific  resist- 
ances, and  we  have  the  projiortion 

required  resistance  :  29.7  :  :  9.032  :  1.594 

IT  •     ,        •  „    -       9032 

Hence,  required  resistance  =  29.7  X  

1.594 

=  168  ohms  (approx.) 

Ans.  168  ohms. 


238 


ELECTRICAL  PRINCIPLES  27 

Calculation  of  Resistance.  From  the  preceding  pages  it  is 
evident  that  resistance  varies  directly  as  the  length,  inversely  as 
the  cross-sectional  area,  and  depends  upon  the  specific  resistance 
of  the  material.  This  may  be  expressed  conveniently  by  the  for- 
mula 

L 
A 

in  which  R  is  the  resistance,  L  the  length  of  the  conductor,  A 
the  area  of  its  cross-section,  and  s  the  specific  resistance  of  the  ma- 
terial. 

Example.  A  telegraph  relay  is  wound  with  1,800  feet  of  wire  .010 
inch  in  diameter,  and  has  a  resistance  of  150  ohms.  What  will  be  its  resist- 
ance if  wound  with  40  feet  of  wire  .022  inch  in  diameter? 

Solution.  If  the  wires  were  of  equal  length,  we  should  have  the  pro- 
portion 

required  resistance:  150  :  :  (.010)^  :  (.022)^ 

(.010)^ 

or,  required  resistance  =  150  X =  30.99  +  ohms 

(.022)2 

For  a  wire  400  feet  long,  we  have,  therefore,  by  direct  proportion, 

400 

required  resistance  = X  30.99  =  6.88  + 

^  1,800 

Ans.  0.88  +  ohms. 

If  a  circuit  is  made  up  of  several  dilTerent  materials  joined  in 
series  with  each  other,  the  resistance  of  the  circuit  is  equal  to  the 
sum  of  the  resistances  of  its  several  parts.  In  calculating  the  re- 
sistance of  such  a  circuit,  the  resistance  of  each  part  should  first 
be  calculated,  and  the  sum  of  these  resistances  will  be  the  total  re- 
sistance of  the  circuit. 

In  Table  I  is  given  the  resistance  of  chemically  pure  substances 
at  0°  centigrade  or  32°  Fahrenheit  in  International  ohms.  The  first 
column  of  numbers  gives  the  relative  resistances  when  that  of  an- 
nealed silver  is  taken  as  unity.  For  example,  mercury  has  62.73 
times  the  resistance  of  annealed  silver.  The  second  and  third  col- 
umns give  the  resistances  of  a  foot  of  wire  .001  inch  in  diameter,  and 
of  a  meter  of  wire  1  millimeter  in  diameter,  respectively.  The 
fourth  and  fifth  columns  give  respectively  the  resistance  in  mi- 
crohms of  a  cubic  inch  and  cubic  centimeter,  that  is,  the  specific  re- 
sistances. 


239 


28 


THE  MOTION  PICTURE 


TABLE  I 

Relative   Resistance  of  Chemically   Pure  Substances  at  32°  F.  Inter= 

national  Olims 


Metals 

Relative 
Resist- 
ance 

Resistance 
of  a  wire 

1  foot  long 
.001  in.  in 
diameter 

Resistance 
of  a  wire 
1  m.  long 
1  mm.  in 
diameter 

Resistance  in 
Micro  Imis 

Cubic 
Inch 

Cubic  Cen- 
timeter 

Silver,  annealed 

1.000 

9.023 

.01911 

.5904 

1.500 

Copper,  annealed 

1.063 

9.585 

.02028 

.6274 

1.594 

Silver,  hard  drawn 

1.086 

9.802 

.02074 

.6415 

1.629 

Copper,  hard  drawn 

1.086 

9.803 

.02075 

.6415 

1.629 

Gold,  annealed 

1.369 

12.35 

.02613 

.8079 

2.052 

Gold,  hard  drawn 

1.393 

12.56 

.02661 

.8224 

2.088 

Aluminum,  annealed 

1.935 

17.48 

.03700 

1.144 

2.904 

Zinc,  pressed 

3.741 

33.76 

.07143 

2.209 

5.610 

Platinum,  annealed 

6.022 

54.34 

.1150 

3.555 

9.032 

Iron,  annealed 

6.460 

58.29 

.1234 

3.814 

9.689 

Lead,  pressed 

13.05 

117.7 

.2491 

7.706 

19.58 

German  silver 

13.92 

125.5 

.2659 

8.217 

20.87 

Platinum-silver  alloy 

(^  platinum,  §  silver) 

16.21 

146.3 

.3097 

9.576 

24.32 

Mercury 

62.73 

570.7 

1.208 

37.05 

94.06 

A  very  small  portion  of  foreign  matter  mixed  with  a  metal 
greatly  increases  its  resistance.  An  alloy  of  two  or  more  metals 
always  has  a  higher  specific  resistance  than  that  of  any  of  its 
con.stituents.  For  example,  the  conductivity  of  silver  mixed  with 
1.2  per  cent  in  volume  of  gold,  will  be  59  when  that  of  pure 
silver  is  taken  as  100.  Annealing  reduces  the  resistance  of 
metals. 

The  following  examples  are  given  to  illustrate  the  use  of  Table 

I  in  connection  with  the  formula  R  =  s -^  and  to  show  the  ap])li- 

cation  of  preceding  laws. 

ExAMFLR.  From  the  .specific  resistance  of  annealed  aluminum  as  given 
in  the  next  to  the  last  column  of  the  tahlc,  calculate  the  resistance  given  in  the 
second  column  of  figures  for  that  substance. 

Solution.  The  resistance  in  microhms  of  a  culiic  inch  of  annealed  alumi- 
num at  32°  F.  is  1.144,  which  is  equal  to  .000001144  ohms.  The  resistance  of 
a  wire  1  foot  long  and  .001  inch  in  diameter  is  recjuired.  According  to  the 
formula  s  =  .000001144,  L  =  1  foot  =  12  inches  and 


4 


3.1416  X  .001^ 


=  .0000007854  sq.  in. 


240 


ELECTRICAL  PRINCIPLES  29 


Substituting  these  values  in  the  formula 
L 


we  have 


R  =  s    ^ 
A 


12 

R  =  .000001144  X 


.0000007854 
=  17.48  ohms  Ans.  17.48  ohms. 

Example.  The  resistance  in  microhms  of  a  cubic  centimeter  of  annealed 
platinum  at  32°  F.  is  9.032.  What  is  the  resistance  of  a  wire  of  the  same 
substance  one  meter  long  and  one  millimeter  in  diameter  at  the  same  temper- 
ature? 

Solution.  In  the  formula  for  resistance  we  have  the  quantities  s  = 
9.032    microhms  =  .000009032    ohms;    L  =  1  meter  =  100  centimeters;    and 

Tzd^      3.1410  X  .1^ 

A  =  —  = =  .007854  sq.  cm. 

4  4  * 

the  diameter  being  equal  to  1  millimeter  =  .1  cm. 

Substituting  these  values  we  have 

100 

R  =  .000009032  X 

.007854 

=  .115  ohm  Ans.  .115  ohm. 

Example.  From  Table  I  the  resistance  of  1  foot  of  pure  annealed  silver 
wire  .001  inch  in  diameter  at  32°  F.  is  9.023  ohms.  What  is  the  resistance  of 
a  mile  of  wire  of  the  same  substance  .1  inch  in  diameter  at  that  temperature? 

Solution.  As  the  resistance  of  wires  is  directly  proportional  to  their 
length  and  inversely  proportional  to  the  squares  of  their  diameters,  the  re- 
quired resistance  is  found  by  multiplying  the  resistance  per  foot  by  5,280  and 
the  product  by  the  inverse  squares  of  the  diameters. 

j  .001    )  2 
Therefore,  R  =  9.023  X  5280  X  j  j" 

=  4. 70  ohms  (approx.) 

Ans.  4.76  ohms. 

Example.  A  mile  and  one-half  of  an  annealed  wire  of  pure  iron  has  a 
resistance  of  46.1  ohms.  What  would  lie  the  resistance  of  hard-drawn  wire 
of  pure  copper  of  the  same  length  and  diameter,  assuming  each  to  be  at  the 
temperature  of  melting  ice? 

Solution.  The  only  factor  involved  by  this  example  is  the  relative  resist- 
ance of  the  two  metals.  From  Table  I,  annealed  iron  has  6.460  and  hard- 
drawn  copper  1.086  times  the  resistance  of  annealed  silver.  Hence,  the  resist- 
ance of  the  copper  is  to  that  of  the  iron  as  1.080  is  to  6.460,  and  the  required 
resistance   is 

1 .080 

R  =  46.1  X =  7.75  ohms  (approx.) 

6.460 

Ans.  7.75  ohms. 


241 


30  'THE  MOTION  PICTURE 

Example.  If  the  resistance  of  a  wire  7,423  feet  long  is  18.7  ohms,  what 
would  be  its  resistance  if  its  length  were  reduced  to  6,253  feet  and  its  cross- 
section  made  one  half  again  as  large? 

Solution.  As  resistance  is  directly  proportional  to  the  length,  and  in- 
versely proportional  to  the  area  of  the  cross-section,  the  required  resistance  is 

02  53         2 

R  =  18.7  X X  —  =10.5  ohms  (approx.) 

7423         3 

Ans.  10.5  ohms. 

Resistance  Affected  by  Heating.  The  resistance  of  metals 
depends  upon  the  temperature,  and  the  resistance  is  increased  by 
heating.  The  heating  of  some  substances,  among  which  is  carbon, 
causes  a  decrease  in  their  resistance.  The  resistance  of  the  fila- 
ment of  an  incandescent  lamp  when  lighted  is  only  about  half  as 
great  as  when  cold.  All  metals,  however,  have  their  resistance  in- 
creased by  a  rise  in  temperature.  The  percentage  increase  in  resist- 
ance with  rise  of  temperature  varies  with  the  different  metals,  and 
varies  slightly  for  the  same  metal  at  different  temperatures.  The 
increase  is  practically  uniform  for  most  metals  throughout  a  con- 
siderable range  of  temperature.  The  resistance  of  copper  increases 
about  .4  per  cent  per  degree  centigrade,  or  about  .22  per  cent  degree 
Fahrenheit.  The  percentage  increase  in  resistance  for  alloys  is  much 
less  than  for  the  simple  metals.  Standard  resistance  coils  are,  there- 
fore, made  of  alloys,  as  it  is  desirable  thnt  their  resistance  should 
be  as  nearly  constant  as  possible. 

The  change  in  resistance  of  one  ohm  per  degree  rise  in  tem- 
perature for  a  substance  is  called  the  temperature  coefficient  for  that 
su Instance.  Table  II  gives  the  temperature  coefficients  for  a  few 
substances. 

If  the  resistance  of  a  conductor  at  a  certain  temperature  is  known, 
the  resistance  the  conductor  will  have  at  a  higher  temperature  may 
be  found  by  multiplying  the  temperature  coefficient  for  the  sub- 
stance, l)y  the  number  of  degrees  increase  and  Ijy  the  resistance  at 
the  lower  temperature,  and  adding  to  this  result  the  resistance  at 
the  lower  temperature.  The  product  of  the  temperature  coefficient 
by  the  number  of  degrees  increase  gives  the  increase  in  resistance 
of  one  ohm  through  that  number  of  degrees,  and  multiplying  this 
by  the  number  of  ohms  gives  the  increase  in  resistance  for  the  conduc- 
tor. The  result  obtained  is  practically  correct  for  moderate  ranges 
of  temperature. 


242 


ELECTRICAL  PRINCIPLES 


31 


TABLE  II 
Temperature  Coefficients 


Mateiiial 

Rise  in  R.  of  1  Ohm  When  Heated         1 

1'  F. 

i^C. 

Platinoid 

Platinum-silver 

German  silver 

Platinum 

Silver 

Copper,  aluminum 

Iron 

.00012 

.00014 

.00022 

.0019 

.0021 

.0022 

.0026 

.00022 

.00025 

.00040 

.0035 

.0038 

.0040 

.0046 

The  above  method  of  calculating  the  resistance  of  conductors 
at  increased  temperature  is  conveniently  expressed  by  the  follow- 
ing formula 

where  R^  is  the  resistance  at  the  higher  temperature,  R^  that  at 
the  lower  temperature,  a  the  temperature  coefficient  for  the  sub- 
stance, anfl  /  the  number  of  degrees  change. 

From  the  preceding  formula  it  follows  that  if  the  resistance 
at  the  higher  temperature  is  known,  that  at  the  lower  temperature 
will  be  given  by  the  formula 


R 


R. 


'      1  +  at 

In  calculating  resistances  at  different  temperatures,  the  tem- 
perature coefficient  based  on  the  Fahrenheit  scale  should  be  used 
if  the  number  of  degrees  change  is  given  in  degrees  Fahrenheit, 
and  that  based  on  the  centigrade  scale  if  given  in  degrees  centi- 
grade. 

Example.  The  resistance  of  a  coil  of  German  silver  wire  at  12°  C.  is 
1 ,304  ohms.    What  would  l)e  its  resistance  at  a  temperature  of  60°  C? 

Solidio7i.     From  the  statement  of  the  example  R^  =  1,304,  /  =  60  —  12 
48,  and  from  Table  II,  a  =  .0004.    Substituting  these  values  in  the  formula 


/? 


2  =  Rj^  {l+at),  we  have 


R^  =  1304  (1  -;-  .0004  X  48) 
=  1304  X  1.0192 
=  1329  ohms  (approx.) 


Ans.  1329  ohms. 


243 


32 


THE  MOTION  PICTURE 


TABLE  III 
American  Wire  Gauge  (B.  &  S.) 


No. 

DiAMETKR   IN 

Circular 
Mils 

Ohms 
per 
1000 
Ft. 

No. 

Diameter  in 

Circular 
Mils 

Ohms 

per 

1000  Ft. 

Mils 

Millim. 

Mils 

Millim. 

0000 

460.00 

11.684 

211600.0 

.051 

19 

35.89 

.912 

1288.0 

8.617 

000 

409.64 

10.405 

167805.0 

.064 

20 

31.96 

.812 

1021.5 

10.566 

00 

364.80 

9.206 

133079.4 

.081 

21 

28.46 

.723 

810.1 

13.323 

0 

324.95 

8.254 

105592.5 

.102 

22 

25.35 

.644 

642.7 

16.799 

1 

289.30 

7.348 

83694.2 

.129 

23 

22.57 

.573 

509.5 

21.185 

2 

257.63 

6.544 

66373.0 

.163 

24 

20.10 

.511 

404.0 

26.713 

3 

229.42 

5.827 

52634.0 

.205 

25 

17.90 

.455 

320.4 

33.684 

4 

204.31 

5.189 

41742.0 

.259 

26 

15.94 

.405 

254.0 

42.477 

5 

181.94 

4.621 

33102.0 

.326 

27 

14.19 

.361 

201.5 

53.563 

6 

162.02 

4.115 

26250.5 

.411 

28 

12.64 

.321 

159.8 

67.542 

7 

144.28 

3.665 

20816.0 

.519 

29 

11.26 

.286 

126.7 

85.170 

8 

128.49 

3.264 

16509.0 

.654 

30 

10.03 

.255 

100.5 

107.391 

9 

114.43 

2.907 

13094.0 

.824 

31 

8.93 

.277 

79.7 

135.402 

10 

101.89 

2.588 

10381.0 

1.040 

32 

7.95 

.202 

63.2 

170.765 

11 

90.74 

2.305 

8234.0 

1.311 

33 

7.08 

.108 

50.1 

215.312 

12 

80.81 

2.053 

6529.9 

1.653 

34 

6.30 

.160 

39.7 

271.583 

13 

71.96 

1.828 

5178.4 

2.084 

35 

5.01 

.143 

31.5 

342.443 

14 

64.08 

1.628 

4106.8 

2.628 

36 

5.00 

.127 

25.0 

431.712 

15 

57.07 

1.450 

3256.7 

3.314 

37 

4.45 

.113 

19.8 

544.287 

IG 

50.82 

1.291 

2582.9 

4.179 

38 

3.96 

.101 

15.7 

686.511 

17 

45.26 

1.150 

2048.2 

5.269 

39 

3.53 

.090 

12.5 

865.046 

18 

40.30 

1.024 

1624.1 

6.645 

40 

3.14 

.080 

9.9 

1091.865 

Example.     If  the  resistance  of  a  copper  conductor  at  95°  F.  is  48.2 
ohms,  what  would  be  the  resistance  of  the  same  conductor  at  40°  F.  ? 

Solution.     In   this  case   i?2  =  48.2,  <  =  95  —  40  =  55,   and  from   Table 

II,  a  =  .0022.    Substituting  these  values  in  the  formula /?j  = 


1  +  0/ 


we  have 


_  48.2 48.2 

*  "  1  +  .0022  X  55 


1.121 
=  43  ohms  (approx.) 

Ans.  43  ohms. 

Table  III  gives  the  resistance  of  the  most  common  sizes  of 
copper  wire  according  to  the  American  or  Brown  and  Sharpe  (B.  & 
S.)  gauge.  Tlie  resistance  given  is  for  pure  copper  wire  at  a  tem- 
perature of  75°  F.  or  24°  C.  The  fourth  cokimn  gives  the  equiva- 
lent number  of  wires  each  one  mil  or  one-thousandth  of  an  inch  in 
diameter.  This  is  called  the  size  of  the  wire  in  circular  mil  and 
is  etjual  to  the  square  of  the  diameter  in  mils.     The  fifth  column 


244 


ELECTRICAL  PRINCIPLES 


33 


gives  the  ohms  per  thousand  feet  and  the  resistance  per  mile  is  found 
by  muUiplying  these  vakies  by  5.28.  Ordinary  commercial  copper 
has  a  conductivity  of  about  95  to  97  per  cent  of  that  of  pure  copper. 
The  resistance  of  commercial  wire  is,  therefore,  about  3  to  5  per  cent 
greater  than  the  values  given  in  Table  III.  The  resistance  for  any 
metal  other  than  copper  may  be  found  by  multiplying  the  resist- 
ance given  in  Table  III  by  the  ratio  of  the  specific  resistance  of 
the  given  metal  to  the  specific  resistance  of  copper. 

Table  IV  gives  the  size  of  the  English  or  Birmingham  wire 
gauge.  The  B.  &  S.  is,  however,  much  more  frequently  used  in  this 
country.  The  Brown  and  Sharpe  gauge  is  a  little  smaller  than  the 
Birmingham  for  corresponding  numbers. 

TABLE  IV 
Stubs'  or  Birmingham  Wire  Gauge  (B.  W.  Q.) 


No. 

Diameter  in          | 

No. 

Diameter  in          | 

No. 

Diameter  in          | 

Mils 

Millim. 

Mils 

Millim. 

Mils 

Millim. 

0000 

454 

11.. 53 

S 

1G5 

4.19 

18 

49 

1.24 

00 

380 

9. 05 

10 

134 

3.40 

20 

35 

0.89 

1 

300 

7.02 

12 

109 

2.77 

24 

22 

0.55 

4 

238 

G.04 

14 

83 

2.11 

30 

12 

0.31 

6 

203 

5.16 

16 

65 

1.65 

30 

4 

0.10 

EXAMPLES   FOR   PRACTICE 

L     Wliat  is  the  resistance  of  an  annealed  silver  wire  90  feet 
long  and  .2  inch  in  diameter  at  32°  F.?  Ans.  .02+  ohm. 

2.  Wliat  is  the  resistance  of  300  meters  of  annealed  iron  wire 
4  millimeters  in  diameter  when  at  a  temperature  of  0°  C? 

Ans.  2.31  +  ohms. 

3.  What  is  the  resistance  of  2  miles  of  No.  27  (B.  &  S.)  pure 
copper  wire  at  75°  F.?  Ans.   565+  ohms. 

4.  The  resistance  of  a  piece  of  cop})er  wire  at  32°  F.  is  3  ohms. 
Wliat  is  its  resistance  at  49°  F.?  Ans.  3.11+  ohms. 

5.  The  resistance  of  a  copptr  wire  at  52°  F.  is  7  ohms,    ^^^lat 
is  its  resistance  at  32°  F.?  Ans.  C.70+  ohms. 

6.  What  is  the  resistance  of  496  ft.  of  No.  10  (B.  &  S.)  pure 
copper  wire  at  45°  F.?  Ans.  .483+  ohms. 


245 


34 


THE  MOTION  PICTURE 


TABLE  V 
Primary  Cells,  Electromotive  Force,  Resistance,  Etc. 


Name 

OF 

Cell 


Volta 
(WoUas- 
ton,  etc.) 


Smee 


Law 


Poggen- 

dorff 
(Grenet) 

Poggen- 

dortr 
(Grenet) 
two  fluid 


Grove 


Bunsen 


Leclanch^ 


Lalande 
Lalande- 
Chaperon 

Upward 


Fitch 


Papst 


Obach 
(dry) 

Daniell 
(Meidin- 
ger  Min- 
otto,  etc.) 

De  la  Rue 

Marie 
Davy 


Clark 
(Standard! 


Anode 


Weston 


Zinc 


Zmc 


Zinc 


Zinc 


Zinc 


Zinc 


Zinc 


Zinc 
Zinc 

Zinc 

Iron 

Zinc 

Zinc 

Zinc 

Zinc 

Zinc 
Cadmium 


Kathode 


Copper 


Platinized 
Silver 


Carbon 


Graphite 
(Carbon) 


Graphite 
(Carbon) 


Platinum 


Graphite 
(Carbon) 

Graphite 
(Carbon) 


Graphite 
(Carbon) 

Graphite 
(Carbon) 


Graphite 
(Carbon) 


Graphite 
(Carbon) 


Graphite 
(Carbon) 


Copper 


Silver 


Graphite 
(Carbon) 


Mercury 
Mercury 


Excitant 


Solution  of 

Sulphuric  Acid 

(HjSO,) 

Solution  of 

Sulphuric  Acid 

(H^SO,) 

Solution  of 

Sulphuric  Acid 

(H.SO,) 

Solution  of 

Sulphuric  Acid 

(H2SO4) 

Saturated  Solu- 
tion of  Potas- 
sium Dichro- 

mate  and 
Sulphuric  Acid 

Sulphuric  Acid 
dilute  (HjSO^) 

Stilphuric  Acid 
dilute  (H2SO4) 

Ammonium 
Chloride 

(NH^Cl) 

Caustic  Potash 

or  Potassium 

Hydrate  (KOH) 

Zinc  Chloride 
(ZnCla) 

Ammoniiun 
Chloride 
(NH^Cl) 

Ferric  Chloride 
(FejClg) 

Ammonium 

Chloride 
(NH.Cl)  in 
Calcium  Sul- 
phate (CaSO^) 

Zinc  Sulphate 
(ZnSO.) 


Ammonium 
Chloride 

Sulphuric  Acid 
dilute  (H2SO4) 


Zinc  Sulphate 
(ZnSo4) 


Cadmium  Sul-    Mercurous  Sul- 
)  III""': -A  phate  (CdS04)  I    hate(Hg2S04) 

*At  15  degrees  centigrade  or  59  degrees  Fahrenheit. 


Depolarizer 


None 


None 


None 


Potassium 
Dichromate 
(KoCrjO.) 


None 
Separate 


Nitric  Acid 
(HNOJ 


Nitric  Acid 


E.  M.  F 

IN 

Volts 


1  to  0.5 


2.1 


1.96 
l.Stol.98 


Internal 
Resist- 
ance   IN 

Ohms 


0.5 


.001  to  .08 


0.1  to  0.12 


Chromic  Acid 


Manganese 
Dioxide 
(MnO.,) 


Cupric  Oxide 


Chlorine  (CI) 

Sodium&Potas- 

sium  Chlorates 

(NaC10,-f 

KCIO3) 

UFe,Cl  ) 


Manganese 
Dioxide 
(MnOJ 


Copper  Sul- 
phate (CuSO.) 


Silver  Chloride 

(AgCl) 

Paste  of  Sul- 
phateofMercurj- 

(IIg2S04) 

Mercurous  Sul- 
phate(Hg,SO^) 


0.08  too. 11 

1.8       10. 1  to  0.12 


1.4  to  1.6  1.13  to  1.15 


0.8  to  0.9 

2.0 
1.1 


1.3 


1.079 


1.03  to 
1.42 


1  52 

1.434* 
1.025 


2  to  5 

0.4  to  0.6 
0.75  to  1 
0.3  to  0.5 


246 


ELECTRICAL  PRINCIPLES 

TABLE  V  (Continued) 


35 


Name 

OF 

Cell 


Von 
Helmholtz 

Chromic 
Acid 
single 
fluid 


Fuller 


GaifiFe 


Maiche 


Niaudet 


Schans- 
chiefE 


Skrivan- 
off 


Anode 


Zinc 


Zinc 


Zinc 


Zinc 

Zinc 

scraps  in 

bath  of 

Mercury 


Zinc 

Zinc 
Zinc 


Kathode 


Mercurv 


Graphite 
(Carbon) 


Graphite 
(Carbon) 

Silver 


Platinized 
Carbon 


Graphite 
(Carbon) 


Graphite 
(Carbon) 


Silver 


Excitant 


Zinc  Cliloride 
(ZnClJ 


Sulphuric  and 

Chromic  Acids, 

dilute  mixed 


Sulphuric  Acid 
(H,SO,) 

Zinc  Chloride 

(ZnCU) 

Common  Salt 
Solution  i.  e. 
Sodium  Chlo- 
ride (NaCl) 

Common  Salt 
Sohuion  i.  e. 

Sodium  Chlo- 
ride (NaCl) 

Mercurial 
Solution 

Caustic  Potash 

or  Potassium 

Hydrate  (KOH) 


Depolarizer 


Mercurous 
Chloride 
(Hg,CL) 


None 
Separate 

Potassium 

Bichromate 

(K.Cr^O,) 

Silver  Chloride 
(AgCl) 


None 
Separate 


Chloride  of 
Calcium 
(Lime) 
(CaClj) 

None 
Separate 

Chloride  of 
Silver 
(AgCl) 


E.  M.  F 

IN 
VOI.TS 


2.2 


1.25 


l.OtO  l.f 


Internai. 
Resist- 
ance IN 
OhM8 


.016  to  .OS 

0.5  to  0.7 
0.5  to  O.G 

1  to  2 

5  to  G 
0.05to0.75 


Resistances  in  last  column  measured  in  cells  standing  6"  X  4" 

Table  V  discloses  among  other  data  the  resistance  of  various 
primary  cells.  The  resistance  of  a  circuit  of  which  a  battery  forms 
a  part  is  made  up  of  the  external  resistance,  or  the  resistance  of  out- 
side wires  and  connections,  and  the  internal  resistance,  or  the  resist- 
ance of  the  battery  itself.  The  terms  anode  and  kathode  appearing 
in  the  second  and  third  columns,  are  commonly  used  with  reference 
to  electrolysis  but  may  also  be  applied  to  primary  cells.  The  current 
pavS-Sjes  from  the  anode  to  the  kathode  through  the  cell  and,  therefore, 
with  reference  to  the  cell  itself,  the  anode  may  be  considered  the  posi- 
tive element  and  the  kathode  the  negative  element.  In  regard  to  the 
outside  circuit,  however,  the  current  passes,  of  course,  from  the  kath- 
ode to  the  anode,  and  hence  with  reference  to  the  outside  circuit  the 
kathode  is  positive  and  the  anode  negative;  ordinarily,  the  external 
circuit  is  considered.  As  the  anode  of  almost  all  primary  cells  is 
zinc  it  may  readily  be  remembered  that  the  current  pa.sses  from  the 
other  element  to  the  zinc  through  the  external  circuit. 


247 


36     '  THE  MOTION  PICTURE 

APPLICATIONS  OF  OHM'S  LAW 

Ohm's  law  is  one  of  the  most  important  and  most  used  laws  of 
electricity. 

Current  is  directly  'proportional  to  the  electromotive  force  and 
inverschj  proportional  to  the  resistance. 

That  is,  if  the  electromotive  force  applied  to  a  circuit  is  increased, 

the  current  will  be  increased  in  the  same  proportion,  and  if  the 

resistance  of  a  circuit  is  increased,  then  the  current  will  be  decreased 

proportionally.     Likewise  a  decrease  in  the  electromotive  force  causes 

a  proportional  decrease  in  current,  and  a  decrease  in  resistance  causes 

a  proportional  increase  in  current.     The  current  depends  only  upon 

the  electromotive  force  and  resistance  and  in  the  manner  expressed 

by  the  above  simple  law.     The  law  may  be  expressed  algebraically 

as  follows 

electromotive  force 

current  a   ^ 

resistance 

The  units  of  these  quantities,  the  ampere,  volt,  and  ohm,  have 
been  so  chosen  that  an  electromotive  force  of  1  volt  applied  to  a 
resistance  of  1  ohm,  causes  1  ampere  of  current  to  flow.  Ohm's 
law  may,  therefore,  be  expressed  by  the  equation 

R 

where  C  is  the  current  in  amperes,  E  the  electromotive  force  in  volts, 
and  R  the  resistance  in  ohms. 

It  is,  therefore,  evident  that  if  the  electromotive  force  and  re- 
sistance are  knowm  the  current  may  be  found,  or  if  any  two  of  the 
three  quantities  are  known  the  third  may  be  found.  If  the  current 
and  resistance  are  known  the  electromotive  force  may  be  found  from 
the  formula 

E  =  RC 

and  if  the  current  and  electromotive  force  are  known,  the  resist- 
ance may  be  found  from  the  formula 

C 
Simple    Applications.     The    following    examples    are   given    to 
illustrate  the  simplest  applications  of  Ohm's  law: 


248 


ELECTRICAL  PRINCIPLES  37 

Example.     If  the  e.  m.  f.  applied  to  a  circuit  is  4  volts  and  its  resist- 
ance is  2  ohms,  what  current  will  flow? 

Solution.     By  the  formula  for  current 

^         E         4 

C  =  —  =  —  =  2  amperes 
R         2  ^ 

Ans.  2  amperes. 

Example.     What  voltage  is  necessary  to  cause  a  current  of  23  amperes  to 

flow  through  a  resistance  of  820  ohms? 

Solution.     By  the  formula  for  e.  m.  f., 

E  ^  RC  =  820  X  23  =  18,860  volts. 

Ans.  18,860  volts. 
Example.     The  e.  m.  f.  applied  to  a  circuit  is  110  volts,  and  it  is  desired 
to  obtain  a  current  of  .6  ampere.    What  should  be  the  resistance  of  the  circuit? 
Solution.     By  the  formula  for  resistance 


E       110 

R  =—r  = =  183.  +  ohms. 

C         .6 


Ans.  183+  ohms. 


Series  Circuits.     A  circuit  made  up  of  several  parts  all  joined 

in  scries  with  each  other,  is  called  a  series  circuit  and  the  resistance  of 

the  entire  circuit  is,  of  course,  the  sum  of  the  separate  resistances.    In 

calculating  the  current  in  such  a  circuit  the  total  resistance  must  first 

be  obtained,  and  the  current  may  then  be  found  by  dividing  the 

applied  or  total  e.  m.  f.  by  the  total  resistance.     This  is  expressed  by 

the  formula 

E 
C  = 


R,  +  R   +  R^-^  etc. 


Example.  Three  resistance  coils  are  connected  in  series  with  each 
other  and  have  a  resistance  of  8,  4  and  17  ohms  respectively.  What  current 
will  flow  if  the  e.  m.  f.  of  the  circuit  is  54  volts? 

Solution.     By   the   preceding   formula 

^  E  54  54 

1.8+  amperes 


R^  +  R2  +  R3        8  +  4  +  17        29 

Ans.  1.8+  amperes. 
Example.     Six  arc  lamps,  each  having  a  resistance  of  5  ohms,  are  con- 
nected in  series  with  each  other  and  the  resistance  of  the  connecting  wires 
and  other  apparatus  is  3.7  ohms.     What  must  be  the  pre.ssure  of  the  circuit 
to  give  a  desired  current  of  9.6  amperes? 

Solution.  The  total  resistance  of  the  circuit  is  72  —  (6  X  5)  +  3.7  = 
33.7  ohms  and  the  current  is  to  be  C  =  9.G  amperes.  Hence,  by  the  formula 
for  e.  m.  f., 

E  =  RC  =  33.7  X  9.6  =  323.+  volts. 

Ans.  323+  volts. 


249 


38 


THE  MOTION  PICTURE 


Ex.\MPLE,  The  current  passing  in  a  certain  circuit  was  12  amperes  and 
the  e.  m.  f.  was  743  volts.  The  circuit  was  made  up  of  4  sections  all  connected 
in  series,  and  the  resistance  of  three  sections  was  16,  9,  and  26  ohms,  respect- 
ively.   What  was  the  resistance  of  the  fourth  section? 

Solution.  Let  x  =  the  resistance  of  the  fourth  section,  then  i?  =  16 
+  9  +  26  +  X  =  51  +  X,  C  =  12,  and  E  =  743.     By  the  formula  for  resistance 


R 


E 


or,  51  +  X 


743 
72^ 


=  61.9  ohms  (approx.) 


If  51  +  X  =  61.9  we  have,  by  transposing  51  to  the  other  side  of  the 
equation 

X  =  61.9  -  51  =  10.9  ohms 

Ans.  10.9  ohms. 
Example.     A  current  of  54  amperes   flowed  through  a  circuit  when 
the  e.  m.  f.  was  220  volts.     What  resistance  should  be  added  in  series  with 
the  circuit  to  reduce  the  current  to  19  amperes? 

Solution.     The  resistance  in  the  first  case  was 

220 
R  = =  4.07  ohms  (approx.) 

The  resistance  in  the  second  must  be 
220 


R 


19 


11.58  ohms  (approx.) 


The  required  resistance  to  insert  in  the  circuit  is  the  difference  of  these 
two  resistances,  or  11.58  —  4.07  =  7.51  ohms. 

Ans.  7.51  ohms. 

Fall  of  Potential  in  a  Circuit.     Fls.  28  illustrates  a  series  circuit 
in  which  the  resistances  A,  B,  C,  D,  and  E  are  connected  in  series 


WVW^ 


WV\AV 


sA'VvVW^ 

Fig.   28.     Baltpry  Circuit  Through  Resistances  in  Series 

with  each  other  and  with  the  source  of  electricity.  If  the  e.  m.  f.  is 
known,  the  current  may  be  found  by  dividing  the  e.  m.  f.  by  the  sum 
of  all  the  resistances.     Ohm's  law  may,  however,  be  applied  to  any 


250 


H 

g  .2 
Q.  t 

**  S  - 

W   o  ^ 

S  "s  2- 

H  So 

0,  ^5 

fe  r  3 

o    .-5 

£5  ^^ 
O  aS 
w  P  s 


ELECTRICAL  PRINCIPLES  39 

part  of  a  circuit  separately,  as  well  as  to  the  complete  circuit.  Sup- 
pose the  resistances  of  A,  B,  C,  D,  and  E  are  4,  3,  6,  3,  and  4  ohms, 
respectively,  and  assume  that  the  source  has  no  resistance.  Suppose 
the  current  flowing  to  be  12  amperes.  The  e.  m.  f.  necessary  to 
force  a  current  of  12  amperes  through  the  resistance  ^  of  4  ohms  is, 
by  applying  Ohm's  law,  equal  to£=7?C=4Xl2  =  48  volts. 
Herice,  between  the  points  a  and  b  outside  of  the  resistance  A,  there 
must  be  a  difference  of  potential  of  48  volts  to  force  the  current  through 
this  resistance.  Also  to  force  the  same  current  through  B,  the  volt- 
age necessary  is  3  X  12  =  36.  Similarly,  for  each  part  C,  D,  and 
E,  there  are  required  72,  36,  and  48  volts,  respectively. 

As  48  volts  are  necessary  for  part  A  and  36  volts  for  part  B, 
it  is  e\'ident  that  to  force  the  current  through  both  parts  a  differ- 
ence of  potential  of  48  +  36  =  84  volts  is  required;  that  is,  the 
voltage  between  the  points  a  and  c  must  be  84  volts.  For  the  three 
parts  A,  B,  and  C,  48  +  36  +  72  =  156  volts  are  necessary,  and 
for  the  entire  circuit,  240  volts  must  be  applied  to  give  the  current  of 
12  amperes.  From  the  above  it  is  evident  that  there  is  a  gradual 
fall  of  potential  throughout  the  circuit,  and  if  the  voltage  between 
any  two  points  of  the  circuit  be  measured,  the  e.  m.  f.  obtained 
would  depend  upon  the  resistance  included  between  these  two  points. 
For  example,  the  voltage  between  points  b  and  d  would  be  found  to 
be  72  +  36  =  108  volts,  or  between  d  and  c,  36  volts,  etc.  From 
the  preceding  it  is  apparent  that  the  fall  of  potential  in  a  part  of 
a  circuit  is  equal  to  the  current  multiplied  by  the  resistance  of 
that  part. 

This  gradual  fall  of  potential,  or  droj)  as  it  is  commonly  called, 
throughout  a  circuit,  enters  into  the  calculations  for  the  size  of  conduct- 
ors or  mains  supplying  current  to  distant  points.  Tlie  resistances 
of  the  conductors  cause  a  certain  drop  in  transmitting  the  current, 
depending  upon  their  size  and  length,  and  it  is,  therefore,  necessary 
that  the  voltage  of  machines  at  the  supply  station  shall  be  great  enough 
to  give  the  voltage  necessary  at  the  receiving  stations  as  well  as  the 
additional  voltage  lost  in  the  conducting  mains. 

For  example,  in  Fig.  28  the  voltage  necessary  between  the 
points  e  and  h  is  144  volts,  l)ut  to  give  this  voltage  the  source  must 
supply  in  addition  the  voltage  lost  in  parts  .1  and  E,  which  equals 
96  volts. 


251 


40  THE  MOTION  PICTURE 

Ex,\MPLE.  The  voltage  required  by  17  arc  lamps  connected  in  series 
is  782  volts  and  the  current  is  6.6  amperes.  The  resistance  of  the  connecting 
wires  is  7  ohms.     What  must  be  the  e.  m.  f.  applied  to  the  circuit? 

Solution.  The  drop  in  the  connecting  wires  isE  =  RC  =  7X  6.6  = 
46.2  volts.    The  e.m.f.  necessary  is,  therefore,  782  +  46.2  =  828.2  volts. 

Ans.  828.2  +  volts. 

Example.  The  source  of  e.  m.  f.  supplies  114  volts  to  a  circuit  made 
up  of  mcandescent  lamps  and  conducting  wires.  The  lamps  require  a  voltage 
of  110  at  their  terminals,  and  take  a  current  of  12  amperes.  What  should 
be  the  resistance  of  the  conducting  wires  in  order  that  the  lamps  will  receive 
the  necessary  voltage? 

Solution.  The  allowable  drop  in  the  conducting  wires  is  114  —  110  =  4 
volts.  The  current  to  pass  through  the  wires  is  12  amperes.  Hence,  the 
resistance  must  be 

E         ^ 

R  = =  ■ — =  .33  4-  ohms 

C         12 

Ans.  .33  ohms. 

Divided  Circuits.  ^Mien  a  circuit  divides  into  two  or  more 
parts,  it  is  called  a  divided  circuit  and  each  part  will  transmit  a 
portion  of  the  current. 

Such  a  circuit  is  illustrated  in  Fig.  29,  the  two  branches  being 
represented  by  h  and  c.  The  current  passes  from  the  positive  pole 
of  the  battery  through  a  and  then  divides;  part  of  the  current  passing 


-]L+ 


Fig.  29.     Divided  Circuits 

through  h  and  part  througli  c.  The  current  then  unites  and  passes 
through  d  to  the  negative  pole  of  the  battery.  The  part  c  may  be 
considered  as  the  main  part  of  the  circuit  and  6  as  a  by-pass  about  it. 
A  branch  which  serves  as  a  by-pass  to  another  circuit  is  called  a 
shunt  circuit,  and  the  two  branches  are  said  to  be  connected  in  farcdlcl. 
In  considering  the  passage  of  a  current  through  a  circuit  of  this 
sort,  it  may  be  necessary  to  determine  how  much  current  will  pass 
through  one  branch  and  how  much  through  the  other.  Evidently 
this  will  depend  upon  the  relative  resistance  of  the  two  branches, 
and  more  current  will  pass  through  the  branch  offering  the  lesser 


252 


ELECTRICAL  PRINCIPLES  41 

resistance  than  through  the  branch  having  the  higher  resistance.  If 
the  two  parts  have  equal  resistances,  then  one-half  of  the  total  cur- 
rent will  pass  through  each  branch.  If  one  branch  has  twice  the 
resistance  of  the  other,  then  only  one-half  as  much  of  the  total  cur- 
rent will  pass  through  that  branch  as  through  the  other;  that  is,  one- 
third  of  the  total  current  will  pass  through  the  first  branch  and  the 
remaining  two-thirds  will  pass  through  the  second. 

The  relative  strength  of  current  in  the  two  branches  luill  he  in- 
versely proportional  to  their  resistances,  or  directly  proportional  to 
their  conductances. 

Suppose  the  resistance  of  one  branch  of  a  divided  circuit  is  r^,  Fig, 
30,  and  that  of  the  other  is  r^.     Then  by  the  preceding  law 


Also, 
and 


current  m  r^  :  current  m  r^ 


current  in  r,  :  total  current  :  :  r^  :  r,  -\-  r. 


current  in  r,  :  total  current  :  :  r,:  r,  i-  r. 


Let  C  represent  the  total  current,  i^  the  current  through  the 
resistance  r^  and  i^  the  current  through  the  resistance  r^.      Then  the 


» 


Fig.   30.     Joint  Resistance  of  a  Divided  Circuit 

two  preceding  proportions  are  expressed  by  the  following  formulas 

Cr,  .  .  Cr, 

2j  = and  ?2  = 


r,  +  r3  r,  +  r^ 

Example.  The  total  current  passing  in  a  circuit  is  24  amperes.  The 
circuit  divides  into  two  branches  having  resistances  of  5  and  7  ohms,  respect- 
ively.   What  is  the  current  in  each  branch? 

Solution.  In  this  case  C  =  24,  r^  =  5,  and  r^  =  7.  Substituting  these 
values  in  the  above  formulas,  we  have 

^H  24  X  7 

I    = —  = =  14  amperes 

^         '"i  +  '"2         5  +  7 

-^'"1  24  X  5 

and  z,  =  ■ * —  = =  10  amperes 

^        T^\r^_  7  +  7 

j  In  .5  ohm  branch,  14  amperes. 
"     "  ohm  branch,  10  amperes. 


j  In  h 
'•  ]  In  7 


253 


42  THE  MOTION  PICTURE 

Joint  Resistance  of  Divided  Circuits.  As  a  divided  circuit  offers 
t^vo  paths  to  the  current,  it  follows  that  the  joint  resistance  of  the 
tAvo  branches  will  be  less  than  the  resistance  of  eitlier  branch  alone. 
The  ability  of  a  circuit  to  conduct  electricity  is  represented  by  its 
conductance,  which  is  the  reciprocal  of  resistance;  and  the  conduct- 
ance of  a  divided  circuit  is  equal  to  the  sum  of  the  conductances  of 
its  parts. 

For  example,  in  Fig.  30,  the  conductance-  of  the  upper  branch 

equals  —  and  that  of  die  lower  branch  equals —  .     If  R   represents 

r  T 

'  1  '2 

the  joint  resistance  of  the  two  parts  then  the  joint  conductance  equals 
1         1   ^_^_^+r. 


R       Tj       r^         r^r^ 

Having  thus  obtained  the  joint  conductance,  the  joint  resist- 
ance is  found  by  taking  the  reciprocal  of  the  conductance,  that  is, 

R  = 


^  +  ^2 

This  formula  may  be  stated  as  follows; 

The  joint  resistance  of  a  divided  circuit  is  equal  to  the  product 
of  the  two  separate  resistances  divided  hy  their  sum. 

For  example,  suppose  the  resistance  of  each  branch  to  be  2 
ohms.     The  conductance  of  the  circuit  will  be, 

—  =  —  +  —  =  1 ,  and  hence  R  =  I  ohm 
R       2        2 

Also  by  the  preceding  formula 

R  = =  1  ohm 

2  +  2 

The  resistance  of  a  divided  circuit  in  which  each  branch  has 
a  resistance  of  2  ohms  is,  therefore,  1  ohm. 

Example.  The  resistances  of  two  separate  conductors  are  3  and  7 
ohms,  respectively.  What  would  be  their  joint  resistance  if  connected  in 
parallel? 

Solution.     In  this  case  r.  =  3  and  rj  =  7,  hence,  by  the  formula 


r.        3X7 

R  = =  2.1  ohms. 

3+7 


Ans.  2.1  ohms. 


254 


ELECTRICAL  PRINCIPLES  43 

Suppose,  as  illustrated  in  Fig.  31,  the  conductors  having  resistances 
equal  to  r^,  r-j,  and  r^,  respectively,  are  connected  in  parallel.  The  joint  total 
conductance  will  then  be  equal  to 

1      _   TVl+Il  '"3    +    '"l  ^2 


1 

1          1 



=  —  -)-  — 

h 

^1              '-2 

and  as  the  joint  resistance  is  the  reciprocal  of  the  joint  conductance,  the  joint 
resistance  R  of  the  three  branches  is  expressed  by  the  formula 


R  = 


ro  i\  +  r,  r„  +  r,  r. 


12 

Example.  What  is  the  joint  resistance  when  connected  in  parallel,  of 
three  wires  whose  respective  resistances  are  41,  52,  and  29  ohms,  respectively? 

Solution.     In   this  case  r^  =  41,  rj  =  52,  and  rg  =  29. 
Hence,  by  the  preceding  formula,  ^ 

41  X   52  X  29 

R  =  — =  12.8+  ohms. 

52  X  29  +  41  X  29  +  41  X  52 

Ans.  12.8+  ohms. 

In  general,  for  any  number  of  conductors  connected  in  parallel, 
the  joint  resistance  is  found  by  taking  the  reciprocal  of  the  sum  of 
the  reciprocals  of  the  separate  resistances. 


Fig.  31.     Triply  Di\-ided  Circuit 

Example.  A  circuit  is  made  up  of  five  wires  connected  in  parallel,  and 
their  separate  resistances  are  respectively  12,  21,  28,  8,  and  42  ohms.  What 
is  the  joint  resistance? 

Solution.     The  sum  of  the  conductances  is- 

1  1  1  1  1     _     53 

U  "^  2T  "*"   28   "^    8  42   ~    168 

Hence  the  joint   resistance  equals 

168 

ie  = =3.1+  ohms 

53 

Ans.  3.1  +  ohms. 
If  the  resistance  of  each  branch  is  known  and  also  the  poten- 
tial difference  between  the  points  of  union,  then  the  current  in  each 
branch  may  be  found  by  applying  Ohm's  law  to  each  branch  sepa- 
rately.     For   example,  if   this   potential   difference   were  96   volts, 


255 


44  THE  MOTION  PICTURE 

and  the  separate  resistances  of  the  4  branches  were  8,  24,  3,  and 
48  ohms,  respectively,  then  the  current  in  the  respective  branches 
would  be  12,  4,  32,  and  2  amperes,  respectively. 

If  the  current  in  each  branch  is  known,  and  also  the  potential 
difi'erence  between  the  points  of  union,  then  the  resistance  of  each 
branch  may  likewise  be  found  from  Ohm's  law. 

The  following  examples  are  given  to  illustrate  the  application 
of  the  preceding  principles. 

EXAMPLES  FOR  PRACTICE 

1.  Two  conductors  having  resistances  of  71  and  19  ohms, 
respectively,  are  connected  in  parallel,  and  the  total  current  pass- 
ino'  in  the  circuit  is  37  amperes.  WTiat  current  passes  in  the  con- 
ductor whose  resistance  is  71  ohms?  Ans.  7.8+  amperes. 

2.  ^^^lat  is  the  joint  resistance  of  two  wires  connected  in  parallel 
if  their  separate  resistances  are  2  and  8  ohms,  respectively? 

Ans.  1.6  ohms. 

3.  AMiat  is  the  joint  resistance  of  three  wires  when  connected 
in  parallel,  whose  separate  resistances  are  5,  7,  and  9  ohms,  re- 
spectively? Ans.  2.2+  ohms. 

4.  Three  wires,  the  respective  resistances  of  which  are  8,  10, 
and  20  ohms,  are  joined  in  parallel.     ^Vllat  is  their  joint  resistance? 

Ans.  3.6+  ohms. 

5.  Four  wires  are  joined  in  parallel,  and  their  separate  re- 
sistances are  2,  4,  6,  and  9  ohms,  respectively.  What  is  the  joint 
resistance  of  the  conductor  thus  formed?  Ans.  .97+  ohms. 

WIRING  METHODS 

PLANNING  AN  INSTALLATION 

The  first  step  in  planning  a  wiring  installation,  is  to  gather  all 
tne  data  which  will  affect  either  directly  or  indirecdy  the  system  of 
wiring  and  the  manner  in  which  the  conductors  are  to  be  installed. 
The  data  will  include:  Kind  of  building;  construction  of  building; 
space  available  for  conductors;  source  and  system  of  electric-current 
supply;  and  all  details  which  will  determine  the  method  of  wiring 
to  be  employed.  These  last  items  materially  affect  the  cost  of  the 
work,  and  are  usually  determined  by  the  character  of  the  building 
and  by  commercial  considerations. 


J5G 


ELECTRICAL  PRINCIPLES  45 

Method  of  Wiring.  In  a  modern  fireproof  building,  the  only 
system  of  wiring  to  be  recommended  is  that  in  which  the  conductors 
are  installed  in  rigid  conduits ;  although,  even  in  such  cases,  it  may  be 
desirable,  and  economy  may  be  effected  thereby,  to  install  the  larger 
feeder  and  main  conductors  exposed  on  insulators  using  weather- 
proof slow-burning  wire.  This  latter  method  should  be  used,  how- 
ever, only  where  there  is  a  convenient  runway  for  the  conductors,  so 
that  they  will  not  be  crowded  and  will  not  cross  pipes,  ducts,  etc.,  and 
also  will  not  have  too  many  bends.  Also,  the  local  inspection  authori- 
ties should  be  consulted  before  using  this  method. 

For  mills,  factories,  etc.,  wires  exposed  on  cleats  or  insulators 
are  usually  to  be  recommended,  although  rigid  conduit,  flexible  con- 
duit, or  armored  cable  may  be  desirable. 

In  finished  buildings,  and  for  extensions  of  existing  outlets, 
where  the  wiring  could  not  readily  or  conveniently  be  concealed, 
moulding  is  generally  used,  particularly  where  cleat  wiring  or  other 
exposed  methods  of  wiring  would  be  objectionable.  However,  as 
has  already  been  said,  moulding  should  not  be  employed  where 
there  is  any  liability  to  dampness. 

In  finished  buildings,  particularly  where  they  are  of  frame  con- 
struction, flexible  steel  conduits  or  armored  cable  are  to  be  recom- 
mended. 

Wliile  in  new  buildings  of  frame  construction,  knob  and  tube 
wiring  is  frequently  employed,  this  method  should  be  used  only 
where  the  question  of  first  cost  is  of  prime  importance.  Wliile  ar- 
mored cable  will  cost  approximately  50  to  100  per  cent  more  than 
knob  and  tube  wiring,  the  former  method  is  so  much  more  perma- 
nent and  is  so  much  safer  that  it  is  strongly  recommended. 

Systems  of  Wiring.  The  system  of  wiring — that  is,  whether 
the  two-wire  or  the  three-wire  system  shall  be  used — is  usually  deter- 
mined by  the  source  of  supply.  If  the  source  of  supply  is  an  isolated 
plant,  with  simple  two-wire  generators,  and  with  little  possibility 
of  current  being  taken  from  the  outside  at  some  future  time,  the 
wiring  in  the  building  should  be  laid  out  on  the  two-wire  system.  If, 
on  the  other  hand,  the  isolated  plant  is  three-wire  (having  three-wire 
generators,  or  two-wire  generators  with  balancer  sets),  or  if  the  cur- 
rent is  taken  from  an  outside  source,  the  wiring  in  the  building  should 
be  laid  out  on  a  three-wire  system. 


257 


46  THE  MOTION  PICTURE 

It  very  seldom  happens  that  current  supply  from  a  central  station 
is  arranged  with  other  than  the  three-wire  system  inside  of  buildings, 
because,  if  the  outside  supply  is  alternating  current,  the  transformers 
are  usually  adapted  for  a  three-wire  system.  For  small  buildings, 
on  the  other  hand,  where  there  are  only  a  few  lights  and  where  there 
would  be  only  one  feeder,  the  two-wire  system  is  used.  As  a  rule, 
however,  when  the  current  is  taken  from  an  outside  source,  it  is  best 
to  consult  the  engineer  of  the  central  station  supplying  the  current, 
and  to  conform  with  his  wishes.  As  a  matter  of  fact,  this  should  be 
done  in  any  event,  in  order  to  ascertain  the  proper  voltage  for  the 
lamps  and  for  the  motors,  and  also  to  ascertain  whether  the  central 
station  will  supply  transformers,  meters,  and  lamps,  for,  if  these 
are  not  thus  supplied,  they  should  be  included  in  the  contract  for  the 
wiring. 

Location  of  Outlets.  A  set  of  plans,  including  elevation  and 
details,  if  any,  and  showing  decorative  treatment  of  the  various  rooms, 
should  be  obtained  from  the  architect.  A  careful  study  should 
then  be  made  by  the  architect,  the  owner,  and  the  engineer,  or  some 
other  person  qualified  to  make  recommendations  as  to  illumination. 
The  location  of  the  outlets  will  depend:  First,  upon  the  decorative 
treatment  of  the  room,  which  determines  the  aesthetic  and  architect- 
ural effects;  second,  upon  the  type  and  general  form  of  fixtures  to  be 
used,  which  should  be  previously  decided  on;  third,  upon  the  tastes 
of  the  oA\niers  or  occupants  in  regard  to  illumination  in  general,  as 
it  is  found  that  tastes  vary  widely  in  regard  to  amount  and  kind  of 
illumination. 

The  location  of  the  outlets,  and  the  number  of  lights  required 
at  each,  having  been  determined,  the  outlets  should  be  marked  on 
the  plans. 

The  architect  should  then  be  consulted  as  to  the  location  of  the 
centers  of  distribution,  the  available  points  for  the  risers  or  feeders, 
and  the  available  space  for  the  branch  circuit  conductors. 

In  regard  to  the  rising  points  for  the  feeders  and  mains,  the  fol- 
lowing precautions  should  be  used  in  selecting  chases: 

The  space  should  be  amply  large  to  accommodate  all  the  feeders  and 
mains  likely  to  rise  at  that  given  point.  This  seems  trite  and  unnecessary 
but  it  is  the  most  usual  trouble  with  chases  for  risers.  Formerly  architects 
and  builders  paid  little  attention  to  the  requirements  for  chases  for  electrical 


258 


ELECTRICAL  PRINCIPLES  47 

work;  but  in  these  later  days  of  2-inch  and  2vV-inch  conduit,  they  realize  that 
these  pipes  are  not  so  invisible  and  mysterious  as  the  force  they  serve  to  dis- 
tribute, particularly  when  twenty  or  more  such  conduits  must  be  stowed 
away  in  a  building  where  no  special  provision  has  been  made  for  them. 

If  possible,  the  space  should  be  devoted  solely  to  electric  wiring.  Steam 
pipes  are  objectionable  on  account  of  their  temperature;  and  these  and  all 
other  pipes  are  objectionable  in  the  same  space  occupied  by  the  electrical 
conduits,  for  if  the  space  proves  too  small,  the  electric  conduits  are  the  first 
to  be  crowded  out. 

The  chase,  if  possible,  should  be  continuous  from  the  cellar  to  the  roof, 
or  as  far  as  needed.  This  is  necessary  in  order  to  avoid  unnecessary  bends  or 
elbows,  which  are  objectionable  for  many  reasons. 

In  similar  manner,  the  location  of  cut-out  cabinets  or  distributing 
centers  should  fulfill  the  following  requirements: 

They  should  be  accessible  at  all  times. 

They  should  be  placed  sufficiently  close  together  to  prevent  the  circuits 
from  being  too  long. 

They  should  not  be  placed  in  too  prominent  a  position,  as  that  is  objec- 
tionable from  the  architect's  point  of  view. 

They  should  be  placed  as  near  as  possible  to  the  rising  chases,  in  order  to 
shorten  the  feeders  and  mains  supplying  them. 

Finished  F^ooi^ 


Fig.  32.     Running  Conductors  Concealed  Under  Floor  in  Fireproof  Building 

Having-  determined  the  system  and  method  of  wiring,  the  location 
of  outlets  and  distributing  centers,  the  next  step  is  to  layout  the  branch 
circuits  supplying  the  various  outlets. 

Before  starting  to  lay  out  the  branch  circuits,  a  drawing  showing 
the  floor  construction,  and  shoTvang  the  space  between  the  top  of  the 
beams  and  girders  and  the  flooring,  should  be  obtained  from  the  archi- 
tect. In  fireproof  buildings  of  iron  or  steel  construction,  it  is  almost 
the  invariable  practice,  where  the  work  is  to  be  concealed,  to  run  the 
conduits  over  the  beams,  under  the  rough  flooring,  carrying  them 
between  the  sleepers  when  running  parallel  to  the  sleepers,  and  notch- 
ing the  latter  when  the  conduits  run  across  them,  Fig.  32.    In  wooden 


259 


48 


THE  MOTION  PICTURE 


frame  buildings,  the  conduits  run  parallel  to  the  beams  and  to  the 
furring,  Fig.  33;  they  are  also  sometimes  run  below  the  beams.  In  the 
latter  case  the  beams  have  to  be  notched,  and  this  is  allowable  only  in 
certain  places,  usually  near  the  points  where  the  beams  are  sup- 
ported. The  architect's  drawing  is,  therefore,  necessary  in  order 
that  the  location  and  course  of  the  conduits  may  be  indicated  on  the 
plans. 

The  first  consideration  in  laying  out  the  branch  circuit  is  the 
number  cf  outlets  and  nuinhcr  cf  lights  to  be  wired  on  any  one  branch 
circuit.  The  Rules  of  the  National  Electric  Code  require  that  "no  set  of 
incandescent  lamps  requiring  more  than  660  watts,  whether  grouped 
on  one  fixture  or  on  several  fixtures  or  pendents,  will  be  dependent  on 
one  cut-out."  \Miile  it  would  be  possible  to  have  branch  circuits 
supplying  more  than  660  watts,  by  placing  various  cut-outs  at  different 
points  along  the  route  of  the  branch  circuit,  so  as  to  subdi\ade  it  into 
small  sections  to  comply  with  the  rule,  this  method  is  not  recommended, 
except  in  certain  cases,  for  exposed  wiring  in  factories  or  mills.  As 
a  nde,  the  proper  method  is  to  have  the  cut-outs  located  at  the  center 


ri-nisVied  rioor-^ 


Stud  or 
Wall 


Tf^I^n^  •  P^Hi-'-.-.-: IJ^V;!-'-';^,' 


]'■<,■  t-^rs::^, 


^ 


Wooflen   Bea-TTi 
Furring  Strips 


-B^wr 


i'*^'.' 


Rough  riooring 
/  Condu.it 


■I*  •'•    f'<--^' 


^ 


Lathing 


/ 


^Plastering 


Stud  or 
Wall 


Fig.  33.     Running  Conductors  Concealed  Under  Fl  oor  in  Wooden  Frame  Building 

of  distribution,  and  to  limit  each  branch  circuit  to  660  watts,  which 
corresj)onds  to  twelve  or  thirteen  50-watt  lamps,  twelve  being  the 
usual  limit.  Attention  is  called  to  the  fact  that  the  inspectors  usually 
allow  50  watts  for  each  socket  connected  to  a  branch  circuit;  and 
although  8-candle-power  lamps  may  be  placed  at  some  of  the  outlets, 
the  inspectors  hold  that  the  stiindard  lamp  is  approximately  50  watts, 
and  for  that  reason  there  is  always  the  likelihood  of  a  lamp  of  that 
capacity  being  used,  and  their  inspection  is  based  on  that  assumption. 
Therefore,  to  comply  with  the  requirements,  an  allowance  of  not 
more  than  twelve  lamps  per  branch  circuit  should  be  made. 


260 


I 


ELECTRICAL  PRINCIPLES  49 

In  ordinary  practice,  however,  it  is  best  to  reduce  this  number 
still  further,  so  as  to  make  allowance  for  future  extensions  or  to  in- 
crease the  number  of  lamps  that  may  be  placed  at  any  outlet.  For 
this  reason,  it  is  wise  to  keep  the  number  of  the  outlets  on  a  circuit  at 
the  lowest  point  consistent  with  economical  wiring.  It  has  been 
proven  by  actual  practice,  that  the  best  results  are  obtained  by  limit- 
ing the  number  to  five  or  six  outlets  on  a  branch  circuit.  Of  course, 
where  all  the  outlets  hav^e  a  single  light  each,  it  is  frequently  neces- 
sary, for  reasons  of  economy,  to  increase  this  number  to  eight,  ten, 
and,  in  some  cases,  twelve  outlets. 

Now,  as  to  the  course  of  the  circuit  work,  little  need  be  said, 
as  it  is  largely  influenced  by  the  relative  position  of  the  outlets,  cut- 
outs, switches,  etc.  Between  the  cut-out  box  and  the  first  outlet,  and 
between  the  outlets,  it  will  have  to  be  decided,  however,  whether 
the  circuits  shall  run  at  right  angles  to  the  walls  of  the  building  or 
room,  or  whether  they  shall  run  direct  from  one  point  to  another, 
irrespective  of  the  angle  they  make  to  the  sleepers  or  beams.  Of 
course,  in  the  latter  case,  the  advantages  are  that  the  cost  is  some- 
what less  and  the  number  of  elbows  and  bends  is  reduced.  If  the 
tubes  are  bent,  however,  instead  of  using  elbows,  the  difference  in 
cost  is  usually  very  slight,  and  probably  does  not  compensate  for  the 
disadvantages  that  would  result  from  running  the  tubes  diagonally. 
As  to  the  number  of  bends,  if  branch  circuit  work  is  properly  laid 
out  and  installed,  and  a  proper  size  of  tube  used,  it  rarely  happens 
that  there  is  any  difference  in  "pulling"  the  branch  circuit  wires. 
It  may  happen,  in  the  event  of  a  very  long  nm  or  one  having  a  large 
number  of  bends,  that  it  might  be  advisable  to  adopt  a  short  and 
more  direct  route. 

Up  to  this  time,  the  location  of  the  distribution  centers  has  been 
made  solely  with  reference  to  architectural  considerations;  but  they 
must  now  be  considered  in  conjunction  with  the  branch  circuit  work. 

It  frequently  happens  that,  after  nmning  the  branch  circuits 
on  the  plans,  we  find,  in  certain  cases,  that  the  position  of  centers  of 
distribution  may  be  changed  to  advantage,  or  sometimes  certain 
groups  may  be  dispensed  with  entirely  and  the  circuits  nm  to  other 
points.  We  now  see  the  wisdom  of  ascertaining  from  the  architect 
where  cut-out  groups  may  be  located,  rather  than  selecting  particular 
points  for  their  location. 


261 


50  THE  MOTION  PICTURE 

As  a  rule,  wherever  possible,  it  is  wise  to  limit  the  length  of  each 
branch  circuit  to  100  feet;  and  the  number  and  location  of  the  dis- 
tributing centers  should  be  determined  accordingly. 

It  may  be  found  that  it  is  sometimes  necessary  and  even  desirable 
to  increase  the  limit  of  length.  One  instance  of  this  may  be  found  in 
hall  or  corridor  lights  in  large  buildings.  It  is  generally  desirable, 
in  such  cases,  to  control  the  hall  lights  from  one  point;  and,  as  the 
number  of  lights  at  each  outlet  is  generally  small,  it  would  not  be 
economical  to  run  mains  for  sub-centers  of  distribution.  Hence, 
in  instances  of  this  character,  the  length  of  runs  will  frequently  exceed 
the  limit  named.  In  the  great  majority  of  cases,  however,  the  best 
results  are  obtained  by  limiting  the  runs  to  90  or  100  feet. 

There  are  several  good  reasons  for  placing  such  a  limit  on  the 
length  of  a  branch  circuit.  To  begin  with,  assuming  that  we  are  going 
to  place  a  limit  on  the  loss  in  voltage  (drop)  from  the  switchboard  to 
the  lamp,  it  may  easily  be  proven  that  up  to  a  certain  reasonable 
limit  it  is  more  economical  to  have  a  larger  number  of  distributing 
centers  and  shorter  branch  circuits,  than  to  have  fewer  centers  and 
longer  circuits.  It  is  usual,  in  the  better  class  of  work,  to  limit  the 
loss  in  voltage  in  any  branch  circuit  to  approximately  one  volt.  As- 
suming this  limit  (one  volt  loss),  it  can  readily  be  calculated  that  the 
number  of  lights  at  one  outlet  which  may  be  connected  on  a  branch 
circuit  100  feet  long  (using  No.  14  B.  &  S.  wire),  is  four;  or  in  the 
case  of  outlets  having  a  single  light  each,  five  outlets  may  be  con- 
nected on  the  circuit,  the  first  being  60  feet  from  the  cut-out,  the  others 
being  10  feet  apart. 

These  examples  are  selected  simply  to  show  that,  if  the  branch 
circuits  are  much  longer  than  100  feet,  the  loss  must  be  increased 
to  more  than  one  volt,  or  else  the  number  of  lights  that  may  be  con- 
nected to  one  circuit  must  be  reduced  to  a  very  small  quantity,  pro- 
vided, of  course,  the  size  of  the  wire  remains  the  same. 

Either  of  these  alternatives  is  objectionable — the  first,  on  the 
score  of  regulation;  and  the  second,  from  an  economical  standpoint. 
If,  for  instance,  the  loss  in  a  branch  circuit  with  all  the  lights  turned 
on  is  four  volts  (assuming  an  extreme  case),  the  voltage  at  which  a 
lainj)  on  that  circuit  burns  will  vary  from  four  volts,  depending  on  the 
innnbcr  of  liglits  burning  at  a  time.  This,  of  course,  will  cause  the 
lanij>  to  burn  below  candle-power  when  all  the  lamps  are  turned  on, 


262 


ELECTRICAL  PRINCIPLES  51 

or  else  to  diminish  its  life  by  burning  above  the  proper  voltage  when 
it  is  the  only  lamp  burning  on  the  circuit.  Then,  too,  if  the  drop  in 
the  branch  circuits  is  increased,  the  sizes  of  the  feeders  and  the  mains 
must  be  correspondingly  increased  (if  the  total  loss  remains  the  same), 
thereby  increasing  their  cost. 

If  the  number  of  lights  on  the  circuit  is  decreased,  we  do  not  use 
to  good  advantage  the  available  carrying  capacity  of  the  wire. 

Of  coarse,  one  solution  of  the  problem  would  be  to  increase  the 
size  of  the  wire  for  the  branch  circuits,  thus  reducing  the  drop.  This, 
however,  would  not  be  desirable,  except  in  certain  cases  where  there 
were  a  few  long  circuits,  such  as  for  corridor  lights  or  other  special 
control  circuits.  In  such  instances  as  these,  it  would  be  better  to 
increase  the  sizes  of  the  branch  circuit  to  No.  12  or  even  No.  10 
B.  &:.  S.  gauge  conductors,  than  to  increase  the  numbers  of  centers 
of  distribution  for  the  sake  of  a  few  circuits  only,  in  order  to  reduce 
the  number  of  lamps  (or  loss)  within  the  limit. 

The  method  of  calculating  the  loss  in  conductors  has  been  given 
elsewhere;  but  it  must  be  borne  in  mind,  in  calculating  the  loss  of  a 
branch  circuit  suppl}ing  more  than  one  outlet,  that  separate  calcu- 
lations must  be  made  for  each  portion  of  the  circuit.  That  is,  a 
calculation  must  be  made  for  the  loss  to  the  first  outlet,  the  length  in 
this  case  being  the  distance  from  the  center  of  distribution  to  the  first 
outlet,  and  the  load  being  the  total  number  of  lamps  supplied  by  the 
circuit.  The  next  step  would  be  to  obtain  the  loss  between  the  first 
and  second  outlet,  the  length  being  the  distance  between  the  two  out- 
lets, and  the  load,  in  this  case,  being  the  total  number  of  lamps  sup- 
plied by  the  circuit,  minvs  the  number  supplied  by  the  first  outlet; 
and  so  on.  The  loss  for  the  total  circuit  would  be  the  sum  of  these 
losses  for  the  various  portions  of  the  circuits. 

Feeders  and  Mains.  If  the  building  is  more  than  one  story,  an 
elevation  should  be  made  showing  the  height  and  number  of  stories. 
On  this  elevation,  the  various  distributing  centers  should  be  sho\Mi 
diagrammatically ;  and  the  current  in  amperes  supplied  through 
each  center  of  distribution,  should  be  indicated  at  each  center.  The 
next  step  is  to  lay  out  a  tentiitive  system  of  feeders  and  mains,  and  to 
ascertain  the  load  in  amperes  supplied  by  each  feeder  and  main. 
The  estimated  length  of  each  feeder  and  main  should  then  be  deter- 
mined, and  calculation  made  for  the  loss  from  the  switchboard  to 


263 


52  THE  MOTION  PICTURE 

each  center  of  distribution.  It  may  be  found  that  in  some  cases  it 
will  be  necessary  to  change  the  arrangement  of  feeders  or  mains,  or 
even  the  centers  of  distribution,  in  order  to  keep  the  total  loss  from 
the  switchboard  to  the  lamps  within  the  limits  previously  determined. 
As  a  matter  of  fact,  in  important  work,  it  is  always  best  to  lay  out  the 
entire  work  tentatively  in  a  more  or  less  crude  fashion,  according  to 
the  "cut-and-dried"  method,  in  order  to  obtain  the  best  results,  be- 
cause the  entire  layout  may  be  modified  after  the  first  preliminary 
layout  has  been  made.  Of  course,  as  one  becomes  mor?  experienced 
and  skilled  in  these  matters,  the  final  layout  is  often  almost  identical 
with  the  first  preliminary  arrangement. 

WIRING  AN  OFFICE  BUILDING 

The  building  selected  as  a  tj-pical  sample  of  a  wiring  installation 
is  that  of  an  office  building  located  in  Washington,  D.  C.  The  figures 
shown  are  reproductions  of  the  plans  actually  used  in  installing  the 
work. 

The  building  consists  of  a  basement  and  ten  stories.  It  is  of 
fireproof  construction,  having  steel  beams  with  terra-cotta  flat  arches. 
The  main  walls  are  of  brick  and  the  partition  walls  of  terra-cotta 
blocks,  finished  with  plaster.  There  is  a  space  of  approximately  five 
inches  between  the  top  of  the  iron  beams  and  the  top  of  the  finished 
floor,  of  which  space  about  3  inches  was  available  for  nmning  the 
electric  conduits.  The  flooring  is  of  wood  in  the  offices,  but  of  concrete, 
mosaic,  or  tile  in  the  basement,  halls,  toilet-rooms,  etc. 

The  electric  current  supply  is  derived  from  the  mains  of  the  local 
illuminating  company,  the  mains  being  brought  into  the  front  of  the 
building  and  extending  to  a  switchboard  located  near  the  center  of  the 
basement. 

As  the  building  is  a  very  substantial  fireproof  structure,  the  only 
method  of  wiring  considered  was  that  in  which  the  circuits  would  be 
installed  in  iron  conduits. 

Electric  Current  Supply.  The  electric  current  supply  is  direct 
current,  two-wire  for  power,  and  three-wire  for  lighting,  having  a 
potential  of  236  volts  between  the  outside  conductors,  and  118  volts 
between  the  neutral  and  either  outside  conductor. 

Switchboard.  On  the  switchboard  in  the  basement  are  mounted 
wattmeters,  provided  by  the  local  electric  company,  and  the  various 


264 


ELECTRICAL  PRINCIPLES  53 

switches  required  for  the  control  and  operation  of  the  lighting  and 
power  feeders.  There  is  a  total  of  ten  triple-pole  switches  for  light- 
ing, and  eighteen  for  power.  An  indicating  voltmeter  and  ampere 
meter  are  also  placed  in  the  switchboard.  A  voltmeter  is  provided 
with  a  double-throw  switch,  and  so  arranged  as  to  measure  the  poten- 
tial across  the  two  outside  conductors,  or  between  the  neutral  con- 
ductor and  either  of  the  outside  conductors.  The  ampere  meter  is 
arranged  with  two  shunts,  one  being  placed  in  each  outside  leg;  the 
shunts  are  connected  with  a  double-pole,  double-throw  switch,  so 
that  the  ampere  meter  can  be  connected  to  either  shunt  and  thus 
measure  the  current  supplied  on  each  side  of  the  system. 

Character  of  Load.  The  building  is  occupied  partly  as  a  news- 
paper office,  and  there  are  several  large  presses  in  addition  to  the  usual 
linotype  machines,  trimmers,  shavers,  cutters,  saws,  etc.  There  are 
also  electrically-driven  exhaust  fans,  house  pumps,  air-compressors, 
etc.  The  upper  portion  of  the  buikling  is  almost  entirely  devoted 
to  offices  rented  to  outside  parties.  The  total  number  of  motors 
supplied  was  55;  and  the  total  number  of  outlets,  1,100,  supplying 
2,400  incandescent  lamps  and  4  arc  lamps. 

Feeders  and  Mains.  The  arrangement  of  the  various  feeders 
and  mains,  the  cut-out  centers,  mains,  etc.,  which  they  supply,  are 
shown  diagrammatically  in  Fig.  34,  which  also  gives  in  schedule  the 
sizes  of  feeders,  mains,  and  motor  circuits,  and  the  data  relating  to  the 
cut-out  panels. 

Although  the  current  supply  was  to  be  taken  from  an  outside 
source,  yet,  inasmuch  as  there  was  a  probability  of  a  plant  being  in- 
stalled in  the  building  itself  at  some  future  time,  the  three-wire  system 
of  feeders  and  mains  was  designed,  with  a  neutral  conductor  equal 
to  the  combined  capacity  of  the  two  outside  conductors,  so  that 
120-volt  two-wire  generators  could  be  utilized  without  any  change  in 
the  feeders. 

Basement.  The  plan  of  the  basement,  Fig.  35,  shows  the  branch 
circuit  wiring  for  the  outlets  in  the  basement,  and  the  location  of  the 
main  s^vitchboa^d.  It  also  shows  the  trunk  cables  for  the  inter- 
connection system  serving  to  provide  the  necessary  wires  for  telephones, 
tickers,  messenger  calls,  etc.,  in  all  the  rooms  throughout  the  building, 
as  will  be  described  later. 

To  avoid  confusion,  the  feeders  were  not  showni  on  the  basement 


265 


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ELECTRICAL  PRINCIPLES 


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Fig.  35.     Wiring  an  Office  Building.    Basement  Plan  Showing  Branch  Circuit  Wiring  for  Out- 
lets in  Basement,  Location  of  Main  Switchboard,  and  Trunk  Cables  of  the  Intercon- 
n3ction  System  Providing  Wires  for  Telephone,  Ticker,  and  Messenger  Call 
Servics,  etc. 


267 


56  THE  MOTION  PICTURE 

plan,  but  were  described  in  detail  in  the  specification,  and  installed 
in  accordance  with  directions  issued  at  the  time  of  installation.  The 
electric  current  supply  enters  the  building  at  the  front,  and  a  service 
switch  and  cut-out  are  placed  on  the  front  wall.  From  this  point,  a 
two-wire  feeder  for  power  and  a  three-wire  feeder  for  lighting,  are 
run  to  the  main  switchboard  located  near  the  center  of  the  basement. 
Owing  to  the  size  of  the  conduits  required  for  these  supply  feeders,  as 
well  as  the  main  feeders  extending  to  the  upper  floors  of  the  building, 
the  said  conduits  are  run  exposed  on  substantial  hangers  suspended 
from  the  basement  to  the  ceiling. 

First  Floor.  The  rear  portion  of  the  building  from  the  basement 
through  the  first  floor,  and  including  the  mezzanine  floor,  between 
the  first  and  second  floors,  at  the  rear  portion  of  the  building  only, 
is  utilized  as  a  press  room  for  several  large  and  heavy  modern 
newspaper  presses.  The  motors  and  controllers  for  these  presses 
are  located  on  the  first  floor.  A  separate  feeder  for  each  of  these 
press  motors  is  run  directly  from  the  main  switchboard  to  the 
motor  controller  in  each  case.  Empty  conduits  were  provided,  ex- 
tending from  the  controllers  to  the  motor  in  each  case,  intended 
for  the  various  control  wires  installed  by  the  contractor  for  the  press 
equipments. 

One-half  of  the  front  portion  of  the  first  floor  is  utilized  as  a  news- 
paper ofiice;  the  remaining  half,  as  a  bank. 

Second  Floor.  The  rear  portion  of  the  second  floor  is  occupied 
as  a  composing  and  linot^'pe  room,  and  is  illuminated  chiefly  by  means 
of  drop-cords  from  outlets  located  over  the  linotype  machines  and 
over  the  compositors'  cases.  Separate  ^-horse-power  motors  are 
provided  for  each  linotype  machine,  the  circuits  for  the  same  being 
run  underneath  the  floor. 

Upper  Floors.  The  upper  floors  are  similar  in  all  respects  with 
the  exception  of  certain  changes  in  partitions,  which  are  not  material 
for  the  purpose  of  illustration  or  for  practical  example.  The  circuit 
work  is  suflficiently  intelligible  from  the  plan  to  require  no  further 
explanation. 

Interconnection  System.  In  the  interconnection  system,  the 
main  interconnection  box  is  located  in  the  basement;  adjoining  this 
main  box  is  located  the  terminal  box  of  the  local  telephone  company. 
A  separate  system  of  feeders  is  provided  for  the  ticker  system,  as  these 


268 


ELECTRICAL  PRINCIPLES 


57 


conductors  require  somewhat  heavier  installation,  and  it  was  thought 
inadvisable  to  place  them  in  the  same  conduits  with  the  telephone 
wires,  owing  to  the  higher  potential  of  ticker  circuits.  A  separate 
interconnection  cable  rims  to  each  floor,  for  telephone  and  messenger 
call  purposes;  and  a  central  box  is  placed  near  the  rising  point  at  each 
floor,  from  which  nm  subsidiary  cables  to  several  points  symmetrically 
located  on  the  various  floors.  From  these  subsidiary  boxes,  wires  can 
be  run  to  the  various  offices  requiring  telephone  or  other  service. 
Small  pipes  are  provided  to  serve  as  race- 
ways from  office  to  office,  so  as  to  avoid 
cutting  partitions.  In  this  way,  wires  can 
be  quickly  provided  for  any  office  in  the 
building  without  damaging  the  building 
in  any  way  whatever;  and,  as  provision 
is  made  for  a  special  wooden  moulding 
near  the  ceiling  to  accommodate  these 
wires,  they  can  be  run  around  the  room 
without  disfiguring  the  walls.  All  the 
main  cables  and  subsidiary  wares  are  con- 
nected with  special  interconnection  blocks  numbered  serially;  and 
a  schedule  is  provided  in  the  main  interconnection  box  in  the  base- 
ment, which  enables  any  wire  originating  thereat,  to  be  readily  and 
conveniently  traced  though  the  building.  All  the  main  cables  and 
subsidiary  cables  are  run  in  iron  conduits. 
OUTLET=BOXES,  CUT=OIJT  PANELS,  AND  OTHER  ACCESSORIES 
Outlet  Boxes.     Before  the  introduction  of  iron  conduits,  outlet- 


Fig.  36.     Universal  and  Knock 
Out  Type  of  Outlet  Box 


Fig.  37.     Water-Tight  Outlet  Box 


boxes  were  considered  unnecessary,  and  with  a  few  exceptions  were 
not  used,  the  conduits  being  brought  to  the  outlet  and  cut  off  after  the 


269 


58 


THE  MOTION  PICTURE 


walls  and  ceilings  were  plastered.  With  the  introduction  of  iron  con- 
duits, however,  the  necessity  for  outlet-boxes  was  realized;  and  the 
Rides  of  the  Fire  Underwriters  were  modified  so  as  to  require  their  use. 
The  Rules  of  the  National  Electric  Code  now  require  outlet-boxes  to 
be  used  with  rigid  iron  and  flexible  steel  conduits,  and  with  armored 
cables.     A  portion  of  the  rule  requiring  their  use  is  as  follows : 

All  interior  conduits  and  armored  cables  must  be  equipped  at  every 
outlet  with  an  approved  outlet-box  or  plate. 

Outlet-plates  must  not  be  used  where  it  is  practicable  to  install  outlet- 
boxes. 

In  buildings  already  constructed,  where  the  conditions  are  such  that 
neither  outlet-box  nor  plate  can  be  installed,  these  appliances  may  be  omitted 
by  special  permission  of  the  inspection  department  having  jurisdiction,  pro- 
viding the  conduit  ends  are  bushed  and  secured. 


Fig.  38. 


Types  of  Floor  Outlet  Boxes 


Fig.  39. 


Fig.  36  shows  a  typical  form  of  outlet-box  for  bracket  or  ceiling 
outlets  of  the  universal  type.  WTien  it  is  desired  to  make  an  opening 
for  the  conduits,  a  blow  from  a  hammer  will  remove  any  of  the  weak- 
ened portion  of  the  wall  of  the  outlet-box,  as  may  be  required.  This 
form  of  outlet-box  is  frequently  referred  to  as  the  knock-out  type. 
Other  forms  of  outlet-boxes  are  made  with  the  openings  cast  in  the 
box  at  the  required  points,  this  class  being  usually  stronger  and  better 
made  than  the  universal  type.  The  advantages  of  the  universal 
type  of  outlet-box  are  that  one  form  of  box  will  serve  for  any  ordinary 
conditions,  the  openings  being  made  according  to  the  number  of 
conduits  and  the  directions  in  which  they  enter  the  box. 

Fig.  37  shows  a  waterproof  form  of  outlet-box  used  out  of  doors, 
or  in  other  places  where  the  conditions  require  the  use  of  a  water- 
tight and  waterproof  outlet-box. 

It  will  be  seen  in  this  case,  that  the  box  is  threaded  for  the  con- 


270 


ELECTRICAL  PRINCIPLES 


59 


duits,  and  that  the  cover  is  screwed  on  tightly  and  a  flange  provided 
for  a  rabber  gasket. 

Figs.  38  and  39  show  water-tight  floor  boxes  which  are  for  outlets 
located  in  the  floor.  A\niile  the  rules  do  not  require  that  the  floor  outlet 


Fig.  40.     Conduit  Bushing 

box  shall  be  water-tight,  it  is  strongly  recommended  that  a  water- 
tight outlet  be  used  in  all  cases  for  floor  connections.  In  this  case 
also,  the  conduit  opening  is  threaded,  as  well  as  the  stem  cover  through 
which  the  extension  is  made  in  the  conduit  to  the  desk  or  table.  ^Mien 
the  floor  outlet  connection  is  not  required, 
the  stem  cover  may  be  removed  and  a  flat 
blank  cover  be  used  to  replace  the  same. 

There  is  hardly  any  limit  to  the  number 
and  variety  of  makes  of  outlet-boxes  on  the 
market,  adapted  for  ordinary  and  for  special 
conditions;  but  the  types  here  illustrated  are  characteristic  and  typ- 
ical forms. 

Bushings.     The  Rules  of  the  National  Electric  Code  require  that 
conduits  entering  junction-boxes,  outlet-boxes,   or  cut-out   cabinets 


Fig.  41.     Lock-Nut 


tii»f»-if 


Fig.  42.     Panel-Box  Terminal  Bushing 

shall  be  provided  with  approved  bushings,  fitted  to  protect  the  wire 
from  abrasion. 

Fig.  40  shows  a  tj^ical  form  of  conduit  bushing.  This  busliing 
is  screwed  on  the  end  of  the  conduit  after  the  latter  has  been  intro- 
duced into  the  outlet-box,  cut-out  cabinet,  etc.,  thereby  forming  an 


271 


60 


THE  MOTION  PICTURE 


insulated  orifice  to  protect  the  wire  at  the  point  where  it  leaves  the 
conduits,  and  to  prevent  abrasion,  grounds,  short  circuits,  etc.  A 
lock-nut.  Fig.  41,  is  screwed  on  the  threaded  end  of  the  conduit  before 

the  conduit  is  placed  in  the  outlet-box 
or  cut-out  cabinet,  and  this  lock-nut 
and  bushing  clamp  the  conduit  securely 
in  position.  Fig.  42  shows  a  terminal 
43  Copper-Tipped  Fuse  Link  ^ushiug  for  pancl-boxcs  uscd  for  flexible 
steel  conduit  or  armored  cable. 

The  Rules  of  the  National  Electric  Code  require  that  the  metal 
of  conduits  shall  be  permanently  and  effectually  grounded,  so  as  to 
insure  a  positive  connection  for  grounds  or  leaking  currents,  and 
in  order  to  provide  a  path  of  least  resistance  to  prevent  the  current 
from  finding  a  path  through  any  source  which  might  cause  a  fire. 
At  outlet-boxes,  the  conduits  and  gas  pipes  must  be  fastened  in  such  a 


Fig.  44.     Edison  Fuse-Plug 


Fig.  45.     Porcelain  Cut-Out  Block 


manner  as  to  insure  good  electrical  connection ;  and  at  centers  of  dis- 
tribution, the  conduits  should  be  joined  by  suitable  bond  wires,  pref- 
erably of  copper,  the  said  bond  wires  being  connected  to  the  metal 


<^- 


% 


Fig.  46.     Enclosed  or  "Cartridge"  Fuse 


structure  of  the  building,  or,  in  case  of  a  building  not  having  an  iron 
or  steel  structure,  being  grounded  in  a  permanent  manner  to  water  or 
gas-piping. 

Fuse=Boxes,  Cut=Out  Panels,  etc.  From  the  very  outset,  the 
necessity  was  apparent  of  having  a  protective  device  in  circuit  with 
the  conductor  to  protect  it  from  overload,  short  circuits,  etc.  For 
this  purpose,  a  fusible  metal  having  a  low  melting  point  was  em- 


272 


ELECTRICAL  PRINCIPLES 


61 


ployed.  The  form  of  this  fuse  has  varied  greatly.  Fig.  43  shows 
a  characteristic  form  of  what  is  knowTi  as  the  link  fuse  with  copper 
terminals,  on  which  is  stamped  the  capacity  of  the  fuse. 


Fig.  47.     Section  of  Enclosed  Fuse 

The  form  of  fuse  used  probably  to  a  greater  extent  than  any  other, 
although  it  is  now  being  superseded  by  other  more  modern  forms, 
is  that  known  as  the  Edison  fuse-plug,  shown  in  Fig.  44.  A  porcelain 
cut-out  block  used  with  the  Edison  fuse  is  showTi  in  Fie-.  45. 

Within  the  last  four  or  five  years,  a  new  form  of  fuse,  known  as 
the  enclosed  fu^e,  has  been  introduced  and  used  to  a  considerable 


Fig.  48.     Porcelain  Cut-Outs  in  Wooden  Box 

extent.  A  fuse  of  this  type  is  shown  in  Fig.  46.  Fig.  47  gives  a  sec- 
tional view  of  this  fuse,  showing  the  porous  filling  surrounding  the 
fuse-strips,  and  also  the  device  for  indicating  when  the  fuse  has 
blown.  This  form  of  fuse  is  made  with  various  kinds  of  terminals; 
it  can  be  used  with  spring  clips  in  small  sizes,  and  with  a  post  screw 
contact  in  larger  sizes.  For  ordinary  low  potentials  this  fuse  is  de- 
sirable for  currents  up  to  25  amperes;  but  it  is  a  debatable  question 


373 


62 


THE  MOTION  PICTURE 


TABLE  VI 
Carrying  Capacity  of  Wires 


Rubber 

Other 

IXSULATION      ' 

Insulation 

B.  &  S.  Gauge 

Circular  Mils 

Amperes 

Amperes 

18 

1,624 

3 

5 

16 

2,583 

6 

8 

14 

4,107 

12 

16 

12 

6,530 

17 

23 

10 

10,380 

24 

32 

8 

16,510 

33 

46 

6 

26,250 

46 

65 

5 

33,100 

54 

77 

4 

41,740 

65 

92 

3 

52,630 

76 

110 

2 

66,370 

90 

131 

1 

83,690 

107 

156 

0 

105,500 

127 

185 

00 

133,100 

150 

220 

000 

167,800 

177 

262 

0000 

211,600 

210 

312 

200,000 

200 

300 

300,000 

270 

400 

400,000 

330 

500 

500,000 

390 

590 

600,000 

450 

680 

700,000 

500 

760 

800,000 

550 

840 

900,000 

600 

920 

1,000,000 

650 

1,000 

1,100,000 

690 

1,080 

1,200,000 

730 

1,150 

1,300,000 

770 

1,220 

1,400,000 

810 

1,290 

1,500,000 

850 

1,360 

1,600,000 

890 

1,430 

1,700,000 

930 

1,490 

1,800,000 

970 

1,550 

1,900,000 

1,010 

1,610 

2,000,000 

1,050 

1,670 

whether  it  is  desirable  to  use  an  enclosed  fuse  for  heavier  currents. 
Fig.  48  shows  a  cut-out  box  with  Edison  phig  fuse-blocks  used  with 
knob  and  tube  wiring.     It  will  be  seen  that  there  is  no  connection 


274 


ELECTRICAL  PRINCIPLES 


63 


compartment  in  this  fuse-box,  as  the  circuits  enter  directly  opposite 
the  terminals  with  which  they  connect. 

Table  VI  shows  the  allowable  carrying  capacity  of  copper  wires 
and  cables  of  ninety-eight  per  cent  conductivity,  according  to  the 
standard  adopted  by  the  American  Institute  of  Electrical  Engineers 
and  must  be  followed  in  placing  interior  conductors. 

For  insulated  aluminum  wire  the  safe-carrying  capacity  is 
84  per  cent  of  that  given  for  copper  wire  with  the  same  kind  of 
insulation. 

The  lower  limit  is  specified  for  mbber-covered  wires  to  pre- 
vent gradual  deterioration  of  the  high  insulations  by  the  heat  of  the 
wires,  but  not  from  fear  of  igniting  the  insulation.  The  question 
of  drop  is  not  taken  into  consideration  in  the  above  tables. 

The  carrying  capacity  of  Xos.  16  and  18,  B.  &  S.  gauge  wire 
is  given,  but  no  smaller  than  No.  14  is  to  be  used,  except  as  allowed 
under  rules  for  fixture  wiring. 

ARC  LAMPS 

Electric  Arc.  Suppose  two  carbon  rods  are  connected  in  an 
electric  circuit,  and  the  circuit  closed  by  touching  the  tips  of  these 
rods  together;  on  separating  the  car- 
bons again  the  circuit  will  not  be 
broken,  provided  the  space  between 
the  carbons  be  not  too  great  but  will 
be  maintained  through  the  arc  formed 
at  these  points.  This  phenomenon, 
which  is  the  basis  of  the  arc  light, 
was  first  obsen'ed  on  a  large  scale  by 
Sir  Humphrey  Davy,  who  used  a  bat- 
tery of  2,000  cells  and  produced  an  arc 
between  charcoal  points  4  inches  apart. 

As  the  incandescence  of  the  car- 
bons across  which  an  arc  is  maintained, 
together  with  the  arc  itself,  forms  the 

source  of  light  for  a  large  portion  of  arc  lamps,  it  will  be  well  to  study 
the  nature  of  the  arc.  Fig.  49  shows  die  general  appearance  of  an 
arc  between  two  carbon  electrodes  when  maintained  by  direct  current. 

Here  the  current  is  assumed  as  passing  from  the  top  carbon  to 


Fig.  49.     The  Electric  Arc  Between 
Carbon  Terminals 


275 


64 


THE  MOTION  PICTURE 


the  bottom  one  as  indicated  by  the  arrow  and  signs.  We  find,  in  the 
direct-current  arc,  that  the  most  of  the  Hght  issues  from  the  tip  of  the 
positive  carbon,  or  electrode,  and  this  portion  is  known  as  the  crater 
of  the  arc.  This  crater  has  a  temperature  of  from  3,000°  to  3,500°  C, 
the  temperature  at  which  the  carbon  vaporizes,  and  gives  fully  80  to 
85  per  cent  of  the  light  furnished  by  the  arc.  The  negative  carbon 
becomes  pointed  at  the  same  time  that  the  positive  one  is  hollowed 
out  to  form  the  crater,  and  it  is  also  incandescent  but  not  to  as  great 
a  degree  as  the  positive  carbon.  Between  the  electrodes  there  is  a 
band  of  violet  light,  the  arc  proper,  and  this  is  surrounded  by  a  lu- 


o 

100 

V^-V"  Ju— A— n"^ — 

90* 

200 

80* 

300 

■4O0 

W 

BOO 

c — Y      \        \/n\  /     \/        /        \\    / 

eoo 

— y'x    3c    ^^     /\ /    \/     / 

60' 

700 

800 

50* 

eoo 

lOOO 

-^foA^^x/ 

Fig.  50. 


Distribution  Curve  for  D.  C.  Arc 
Lamp  (Vertical  Plane) 


minous  zone  of  a  golden  yellow  color.  The  arc  proper  does  not  fur- 
nish more  than  5  per  cent  of  the  light  emitted  when  pure  carbon 
electrodes  are  used. 

The  carbons  are  worn  away  or  consumed  by  the  passage  of  the 
current,  the  positive  carbon  being  consumed  about  twice  as  rapidly 
as  the  negative. 

The  light  distribution  curv^e  of  a  direct-current  arc,  taken  in  a 
vertical  plane,  is  shown  in  Fig.  50.  Here  it  is  seen  that  the  maxi- 
mum amount  of  light  is  given  off  at  an  angle  of  about  50°  from  the 
vertical,  the  negative  carbon  shutting  off  the  rays  of  light  that  are 
thrown  directly  downward  from  the  crater. 

If  alternating  current  is  used,  the  upper  carbon  becomes  positive 
and  negative  alternately,  and  there  is  no  chance  for  a  crater  to  be 


276 


f 


ELECTRICAL  PRINCIPLES 


65 


foiTaed,  both  carbons  giving  off  the  same  amount  of  light  and  being 
consumed  at  about  the  same  rate.  The  light  distribution  curve  of 
an  alternating-current  arc  is  shown  in  Fig.  5L 

Arc=Lamp  Mechanisms.     In  a  practical  lamp  we  must  have  not 
only  a  pair  of  carbons  for  producing  the  arc,  but  also  means  for  sup- 


Fig.  51.     Distribution  Curve  for  A.  C.  Arc  Lamp  (Vertical  Plane) 

porting  these  carbons,  together  with  suitable  arrangements  for  leading 
the  current  to  them  and  for  maintaining  them  at  the  proper  distance 
apart.  The  carbons  are  kept  separated  the  proper  distance  by  the 
operating  mechanisms  which  must  perform  the  following  functions: 

1.  The  carbons  must  be  in  contact,  or  be  brought  into  contact,  to  start 
the  arc  when  the  current  first  flows. 

2.  They  must  be  separated  at  the  right  distance  to  form  a  proper  arc 
immediately   afterward. 

3.  The  carbons  must  be  fed  to  the  arc  as  they  are  consumed. 

4.  The  circuit  should  be  open  or  closed  when  the  carbons  are  entirely 
consumed,  depending  on  the  method  of  power  distribution. 

The  feeding  of  the  carbons  may  be  done  by  hand,  as  is  the  case 
in  some  stereopticons  using  an  arc,  but  for  ordinary  illumination  the 


277 


66 


THE  MOTION  PICTURE 


+   -<0) 


A/wwwwwwv 


^. 


^ 


H 


Sn 


striking  and  maintaining  of  the  arc  must  be  automatic.  It  is  made 
so  in  all  cases  by  means  of  solenoids  acting  against  the  force  of  gra\aty 
or  against  springs.     There  is  an  endless  number  of  such  mechanisms, 

but  a  few  only  will  be  described 
here.  They  may  be  roughly  di- 
vided into  three  classes:  shunt 
mechanisms,  series  mechanisms, 
differential  mechanisms. 

Shunt  Mechanisms,  In  shunt 
lamps,  the  carbons  are  held  apart 
before  the  current  is  turned  on, 
and  the  circuit  is  closed  through 
a  solenoid  connected  in  across 
the  gap  so  formed.  All  of  the 
current  must  pass  through  this 
coil  at  first,  and  the  plunger  of 
the  solenoid  is  arranged  to  draw 
the  carbons  together,  thus  starting 
the  arc.  The  pull  of  the  solenoid 
and  that  of  the  springs  are  ad- 
justed to  maintain  the  arc  at  its 
proper  length. 

Such   lamps   have    the   disad- 
vantage of   a  high  resistance  at 
the  start — 450   ohms  or  more — 
and  are  difficult  to  start  on  series 
circuits,  due  to  the  high  voltage  required.     They  tend  to  maintain 
a  constant  voltage  at  the  arc,  but  do   not  aid  the  d}Tiamo  in  its 
regulation,  so  that  the  arcs  are  liable  to  be  a  little  unsteady. 

Series  Mechanisms.  With  the  series-lamp  mechanism  the  carbons 
are  together  when  the  lamp  is  first  started  and  the  current,  flowing  in 
the  series  coil,  separates  the  electrodes,  striking  the  arc.  When  the 
arc  is  too  long,  the  resistance  is  increased  and  the  current  lowered,  so 
that  the  pull  of  the  solenoid  is  weakened  and  the  carbons  feed  together. 
This  type  of  lamp  can  be  used  only  on  constant-potential  systems. 
Fig.  52  shows  a  diagram  of  the  connection  of  such  a  lamp.  This 
diagram  is  illustrative  of  the  connection  of  one  of  the  lamps  manu- 
factured by  the  Western  Electric  Company,  for  use  on  a  direct-current. 


t 


Fig.  52. 


Series  Mechanism  for  D.  C. 
Arc  Lamp 


278 


ELECTRICAL  PRINCIPLES 


67 


constant-potential  system.  The  symbols  +  and  —  refer  to  the  termi- 
nals of  the  lamp,  and  the  lamp  must  be  so  connected  that  the  current 
flows  from  the  top  carbon  to  the  bottom  one.  jR  is  a  series  resistance, 
adjustable  for  different  voltages  by  means  of  the  shunt  G.  F  and  D 
are  the  controlling  solenoids  connected  in  series  with  the  arc.  B  and 
C  are   the  positive  and  negative  carbons  re-  _ 

spectively,  while  A  is  the  switch  for  turning 
the  current  on  and  off.  H  is  the  plunger  of 
the  solenoids  and  /  the  carbon  clutch,  this 
being  what  is  known  as  a  carbon-feed  lamp. 
The  carbons  are  together  when  A  is  first 
closed,  the  current  is  excessive,  and  the 
plunger  is  dra^\ni  up  into  the  solenoids,  lift- 
ing the  carbon  B  until  the  resistance  of  the 
arc  lowers  the  current  to  such  a  value  that 
the  pull  of  the  solenoids  just  counter-balances 
the  weight  of  the  plunger  and  carbon.  G 
must  be  so  adjusted  that  this  point  is  reached  Fig.  53.  Differential  Mechan- 

,  ,1  •        J    'j  11  ji  ism  for  D.  C.  Arc  Lamp 

when  the  arc  is  at  its  normal  length. 

Diferential  Mechanisms.  In  the  differential  lamp,  the  series  and 
shunt  mechanisms  are  combined,  the  carbons  being  together  at  the 
start,  and  the  series  coil  arranged  so  as  to  separate  them  wliile  the 
shunt  coil  is  connected  across  the  arc,  as  before,  to  prevent  the  car- 
bons from  being  drawn  too  far  apart.  This  lamp  operates  only  over 
a  low-current  range,  but  it  tends  to  aid  the  generator  in  its  regulation. 

Fig  53  shows  a  lamp  having  a  differential  control,  this  also  being 
the  diagram  of  a  Western  Electric  Company  arc  lamp  for  a  direct- 
current,  constant-potential  system.  Here  S  represents  the  shunt  coil 
and  ^1/  the  series  coil,  the  armature  of  the  two  magnets  A  and  A'  being 
attached  to  a  bell-crank,  pivoted  at  B,  and  attached  to  the  carbon 
clutch  C.  The  pull  of  coil  S  tends  to  lower  the  carbon  while  that  of 
M  raises  the  carbon,  and  the  two  are  so  adjusted  that  equilibrium  is 
reached  when  the  arc  is  of  proper  length.  All  of  the  lamps  are 
fitted  with  an  air  dashpot,  or  some  damping  device,  to  prevent  too 
rapid  movements  of  the  working  parts. 

The  methods  of  supporting  the  carbons  and  feeding  them  to 
the  arc  may  be  divided  into  two  classes:  rod-feed  mechanism, 
carbon-feed  mechanism. 


279 


68 


THE  MOTION  PICTURE 


Rod-Feed  Mechanism,  Lamps  using  a  rod-feed  have  the  upper 
carbons  supported  by  a  conducting  rod,  and  the  regulating  mechan- 
ism acts  on  this  rod,  the  current  being  fed  to  the  rod  by  mean^ 
of  sHding  contact.     Fig.  54  shows  the  arrangement  of  this  type  of 

feed.  The  rod  is  shown  at  /?, 
the  shding  contact  at  B,  and  the 
carbon  is  attached  to  the  rod  at  C. 
These  lamps  have  the  ad- 
vantage that  carbons,  which  do 
not  have  a  uniform  cross-section 
or  smooth  exterior,  may  be  used, 
but  they  possess  the  disadvantage 
of  being  very  long  in  order  to  ac- 
commodate the  rod.  The  rod  must 
also  be  kept  clean  so  as  to  make 
a  good  contact  with  the  brush. 

Carbon-Feed  Mechanism.  In 
carbon-feed  lamps  the  controlling 
mechanism  acts  on  the  carbons 
directly  through  some  form  of 
clutch  which  grips  the  carbon 
when  it  is  lifted, but  allows  the  car- 
bon to  slip  through  it  when  the 
tension  is  released.  For  this  t^^x 
of  feed  the  carbon  must  he 
straight  and  have  a  uniform  cross- 
section  as  well  as  a  smooth  exterior.  The  current  may  be  led  to 
the  carbon  by  means  of  a  flexible  lead  and  a  short  carbon  holder. 

MOVINQ=PICTURE  MACHINES 

Arc  Lamp.  Arc  lamp  used  as  a  part  of  moving  picture  machines 
must  be  constructed  similar  to  arc  lamps  of  theaters,  and  wiring  of 
same  must  not  be  of  less  capacity  than  No.  6  B.  &  S.  gauge. 

Arc  lamps  used  for  stage  effects  must  conform  to  the  following 
requirements: 

a.  Must  be  constructed  entirely  of  metal  except  where  the  use 
of  approved  insulating  material  is  necessary. 

b.  Must  be  substantially  constructed,  and  so  designed  as  to 


Fig.  54.     Rod-Feed  Mechanism 


280 


ELECTRICAL  PRINCIPLES  69 

provide  for  proper  ventilation,  and  to  prevent  sparks  being  emitted 
from  lamps  when  same  is  in  operation,  and  mica  must  be  used  for 
frame  insulation. 

c.  Front  opening  must  be  provided  with  a  self-closing  hinged 
door  frame  in  which  wire  gauze  or  glass  must  be  inserted,  excepting 
lens  lamps,  where  the  front  may  be  stationary,  and  a  solid  door  be 
provided  on  back  or  side. 

d.  Must  be  provided  with  a  one-sixteenth-inch  iron  or  steel 
guard  having  a  mesh  not  larger  than  1  inch,  and  be  substantially 
placed  over  top  and  upper  half  of  sides  and  back  of  lamp  frame;  this 
guard  to  be  substantially  riveted  to  frame  of  lamp,  and  to  be  placed  at 
a  distance  of  at  least  2  inches  from  the  lamp  frame. 

e.  Switch  on  standard  must  be  so  constructed  that  accidental 
contact  with  any  live  portion  of  same  will  be  impossible. 

/.  All  stranded  connections  in  lamp  and  at  switch  and  rheo- 
stat must  be  provided  with  approved  lugs. 

g.  Rheostat,  if  mounted  on  standard,  must  be  raised  to  a  height 
of  at  least  3  inches  above  floor  line,  and  in  addition  to  being 
properly  enclosed  must  be  surrounded  with  a  substantially  attached 
metal  guard  having  a  mesh  not  larger  than  1  square  inch,  which 
guard  is  to  be  kept  at  least  1  inch  from  outside  frame  of  rheostat. 

h.  A  competent  operator  must  be  in  charge  of  each  arc  lamp, 
except  that  one  operator  may  have  charge  of  two  lamps  when  they 
are  not  more  than  10  feet  apart,  and  are  so  located  that  he  can  prop- 
erly watch  and  care  for  both  lamps. 

Miscellaneous.  Rheostats  must  conform  to  rheostat  require- 
ments for  theater  arcs. 

To'p  reel  must  be  encased  in  a  steel  box  with  a  hole  at  the  bottom 
only  large  enough  for  film  to  pass  through,  and  cover  so  arranged  that 
this  hole  can  be  instantly  closed.  No  solder  to  be  used  in  the  con- 
struction of  this  box. 

A  steel  box  must  be  used,  for  receiving  the  film  after  being  shown, 
with  a  hole  in  the  top  only  large  enough  for  the  film  to  pass  through 
freely,  with  a  cover  so  arranged  that  this  hole  can  be  instantly  closed. 
An  opening  may  be  placed  at  the  side  of  the  box  to  take  the  film 
out,  with  a  door  hung  at  the  top,  so  arranged  that  it  cannot  be  en- 
tirely opened,  and  provided  with  spring  catch  to  lock  it  closed.  No 
solder  to  be  used  in  the  construction  of  this  box. 


281 


70  THE  MOTION  PICTURE 

The  handle  or  crank  vised  in  operating  the  machine  must  be 
secured  to  the  spindle  or  shaft,  so  that  there  will  be  no  hability  of  its 
coming  off  and  allowing  the  film  to  stop  in  front  of  lamp. 

A  shutter  must  be  placed  in  front  of  the  condenser,  arranged  so 
as  to  be  readily  closed. 

Extra  films  must  be  kept  in  metal  box  with  tight-fitting  cover. 

Machines  must  be  operated  by  hand  (motor  driven  will  not  be 
permitted). 

Picture  machine  must  be  placed  in  an  enclosure  or  house  made 
of  suitable  fireproof  material,  be  thoroughly  ventilated  and  large 
enough  for  operator  to  walk  freely  on  either  side  of  or  back  of  ma- 
chine. All  openings  into  this  booth  must  be  arranged  so  as  to  be 
entirely  closed  by  doors  or  shutters  constructed  of  the  same  or 
equally  good  fire-resisting  material  as  the  booth  itself.  Doors  or 
covers  must  be  arranged  so  as  to  be  held  normally  closed  by  spring 
hinges  or  equivalent  devices. 

*MERCURY=ARC  RECTIFIERS  FOR  MOTION  PICTURES 

One  of  the  most  important  factors  contributing  to  the  success 
of  a  motion-picture  theater  is  the  quality  and  brilliancy  of  the  light 
projected  from  the  lamps.  For  pleasing  effect  motion  pictures  re- 
quire a  steady,  white  light  of  sufficient  intensity  to  bring  out  the 
natural  light  and  color  values  of  the  films,  and  the  theater  having 
the  best  quality  of  light  stands  the  best  show  of  getting  the  biggest 
patronage.  It  is  well  known  that  the  light  obtained  from  the  direct- 
current  is  much  superior  to  that  from  the  alternating-current  arc 
lamps.  However,  until  recently  all  those  who  could  obtain  only 
alternating-current  supply  have  got  along  with  the  poorer  quality  of 
light  simply  for  the  lack  of  apparatus  for  economically  converting 
alternating  current  into  direct  current. 

In  Fig.  55  is  shown  a  mercury-arc  rectifier  developed  by  the 
General  Electric  Company  for  furnishing  current  of  the  desired  char- 
acter at  a  cost  less  than  that  of  the  most  economically  operated 
alternating-current  arc  lamp. 

There  are  certain  facts  which  should  be  borne  in  mind  while 
making  an  analysis  of  the  cost  of  producing  a  given  intensity  of  pro- 
jected light  from  alternating  current,  direct  current,  and  rectified 


*By  courtesy  of  the  McGraw  Publishing  Company. 


282 


I 


» 


ELECTRICAL  PRINCIPLES 


71 


current  with  the  most  approved  devices  applicable  in  each  case. 
For  instance,  the  best  class  of  motion  pictures  requires  a  light  in- 
tensity of  upward  of  8,000  candle  power,  and  as  5,000  candle  power 
is  the  maximum  obtainable  from  alternating  current  with  the  best 
auto-transformers,  or  the  highest  current  values  practicable,  it  is 
evident  (hat  the  use  of  alternating  current  under  such  conditions  is 


Fig.  55.     Front  and  Back  Views  of  Mercury-Arc  Rectifier  for  Moving-Picture  Machine 

entirely  satisfactory-  owing  to  the  insufficiency  of  the  light.  Where 
direct-current  supply  is  obtainable,  some  have  found  relief  by  using 
it,  but  their  experience  has  served  to  emphasize  the  prohibitory 
effect  of  the  additional  cost  entailed  by  the  loss  of  at  least  60  per 
cent  of  the  energy  drawn  from  the  line  in  the  resistance  or  rheostat 
employed  to  regulate  the  current  in  the  arc. 

These  facts  serve  to  define  the  limitations  of  both  the  alternating- 


283 


72  THE  MOTION  PICTURE 

current  and  the  direct-current  arc  relative  to  motion-picture  light- 
ing, but  in  order  to  give  the  various  alternating-current  methods  a 
fair  basis  for  comparison,  assume  that  a  light  intensity  of  5,000 
candle  power  is  required.  From  actual  determinations  carefully 
made  it  is  found  that  to  obtain  5,000  candle  power  from  a  110- 
volt  alternating-current  circuit  with  rheostats  requires  7  kilowatts; 
a  110- volt  direct-current  circuit  with  rheostat  requires  2.25  kilowatts; 
an}^  alternating-current  circuit  with  auto-transformer  requires  2.1 
kilowatts,  and  with  mercury-arc  rectifier  requires  1.7  kilowatts. 

Since  auto-transformers  are  extensively  used  in  alternating- 
current  supply  systems  to  obtain  a  substantial  reduction  in  energy 
consumption,  the  method  of  using  alternating  current  with  rheostats 
may  be  considered  as  obsolete,  and  since  a  prohibitory  amount  of 
energy  is  wasted  in  using  direct  current  with  a  rheostat,  that  method 
can  be  omitted  from  present  consideration.  This  affords  a  direct 
comparison  between  the  alternating  current  with  the  use  of  econo- 
mizers on  the  one  hand  and  mercury-arc  rectifiers  on  the  other. 

The  figures  given  above  show  a  difference  of  400  watts  in  favor 
of  the  mercury-arc  rectifier.  This  means  than  on  the  basis  of  an 
average  daily  run  of  seven  hours  at  a  cost  of  6  cents  a  kilowatt-hour 
the  use  of  a  mercury-arc  rectifier  provides  a  light  having  all  the 
advantages  of  that  given  by  a  direct-current  arc  at  a  cost  of  at  least 
$60  per  year  less  than  that  obtained  from  alternating  current  with 
the  best  type  of  auto-transformer. 

Furthermore,  it  is  evident  that  when  the  light  intensity  required 
exceeds  5,000  candle  power,  thus  rendering  the  alternating-current 
method  inapplicable,  the  saving  effected  by  the  use  of  the  mercury- 
arc  rectifier  as  compared  to  the  cost  of  using  direct  current  with  a 
rheostat  is  much  more  significant.  For  instance,  to  obtain  7,500 
candle  power  requires  3.1  kilowatts  from  direct  current  with  rheostat 
and  2.15  kilowatts  from  alternating  current  with  mercury-arc  rec- 
tifier. The  difference  in  favor  of  the  mercury-arc  rectifier  is  950 
watts,  which  means  a  saving  of  at  least  $145  per  year. 

In  addition  to  the  positive  money-saving  capability  of  the 
device,  the  excellent  light  of  practically  any  candle-power  obtainable 
from  alternating-current  supply  and  the  reliability,  ease,  and  safety 
of  operation  render  the  mercury-arc  rectifier  particularly  desirable  for 
making  pleasing  and  successful  "photo  plays." 


284 


INDEX 


The  page  num^'ers  of  this  volume  will  be  found  at  the  bottom  of  the 
pages;  the  numbers  at  the  top  refer  only  to  the  section. 


] 

Part 

Page 

Part 

Page 

A 

Arc  lamps 

II, 

275 

Aberration 

n, 

20 

electric  arc 

II, 

275 

Acetylene 

I, 

16 

mechanisms 

II, 

277 

Actors 

II, 

105 

Astigmatism 

II, 

22 

starring  an  actor 

II, 

106 

Atlas  Film  Company 

I, 

278 

stock  companies 

II, 

105 

Author 

II, 

76 

Adjustable  lens 

I, 

94 

his  problems 

II, 

77 

Advertising 

II, 

197 

art,  limitations  of 

II, 

77 

Advertising  drop  curtain 

II, 

207 

plot 

II, 

77 

Advertising  slides 

II, 

207 

scenario 

II, 

78 

Airdome 

II, 

195 

who  is 

II, 

95 

Ajax  Film  Company 

I, 

277 

Autochrome  plates 

II, 

65 

Alignment  masks 

I, 

42 

Automatic  music 

II, 

203 

Alternating-current  arc 

I, 

19 

Automatic  shutter 

I, 

159 

Ambrosio  Film  Manufacturing 

Auxiliary  rheostat 

I, 

47 

Company 

I, 

277 

Auxiliary   rheostat   for  double 

American  Cinephone  Company 

I, 

277 

lantern 

I, 

48 

American  Film     Manufactur- 

Auxiliary switch 

I, 

49 

ing  Company 

I, 

277 

American  Kinograph  Company 

I, 

277 

B 

American  Motor  Racing  Pic- 

ture Company 

I, 

278 

Barker  Motion  Photography 

278 

American  Mutoscope  and  Bio- 

Barrel  shutter 

97 

graph  Company 

I, 

278 

Bat  films 

278 

Animated  Motion-Picture  Pat- 

Bavaria Film  Manufacturing 

ents  Company 

I, 

278 

Company 

278 

Animatophone  Syndicate 

I, 

278 

Beater  movement 

113 

Announcement  slides           I,  72 

;  II 

199 

Pitman  type 

114 

Aquila    Film     Manufacturing 

spring-bar  type 

114 

Company 

I, 

278 

wrist-pin  type 

114 

Arc 

Before-t  he-lens  shutter 

98 

alternating-current 

I, 

19 

Bianchi  camera 

ii! 

140 

direct-current 

I, 

17 

Bichromatic  cell 

II, 

226 

electric 

I, 

17 

"Biograph"  film 

278 

Arc-lamp  mechanism 

II, 

277 

"Bison" 

11, 

278 

differential  mechanism 

11, 

279 

Blue  prints 

II, 

55 

rod-feed  mechanism 

II, 

280 

Bushings 

II, 

271 

series  mechanism 

II, 

278 

W.  Butcher  &  Sons 

11, 

278 

Note. — For  page  numbers  see  foot  of  pages. 


285 


INDEX 


Part  Page 


Part  Page 


c 

Chromatic  aberration 

II, 

Calcium  or  gaso-oxygen 

light       ] 

[,     152 

Chronophotography                II, 

69, 

Camera 

II, 

11,  122 

motographic  microscopy 

11, 

buying 

11 

[,        13 

motographic     ultramicros- 

construction  of 

I] 

14 

copy 

II, 

exposed    and    unexposed 

X-ray  motography 

II, 

films 

[,     126 

Cinephone 

I, 

film  movement 

[,     12.3 

Cinephone,  operation  of 

I, 

loading 

,     127 

Claw  movement 

I, 

loading  film  holders 

[,     125 

Clement,  E.  G. 

I, 

talking-picture 

[,     257 

Color,  production  of 

I, 

Camera  man 

[,      122 

Colored  photographs 

il, 

Camera  man's  duties 

[,     128 

Coloring  films 

11, 

control  of  image 

[,     133 

hand  process 

II, 

duplicate  exposures 

[,     138 

machine  process 

11, 

exposure  control 

L,     134 

stencil  process 

11, 

exposure  meters 

[,     136 

Colormotography 

I, 

exposure  time 

[,     134 

Friese-Green  process 

I, 

finders 

L,     139 

color  shutter 

I, 

focusing 

[,     132 

development  of  system 

I, 

indicator 

[,     139 

manufacture 

I, 

lens  length 

[,     131 

projection  of  film 

I, 

marker 

[,     139 

splices 

I, 

reversing 

[,     139 

Urban-Smith  process 

I, 

setting  up  camera 

[,     131 

alternate  projection 

I, 

shutter 

[,     133 

Kinemacolor  machine 

I, 

taking  picture 

[,     128 

making       Kinemacolor 

trick  crank 

[,     138 

film  pictures 

I, 

turning  crank 

[,     129 

production  of  color 

I, 

Camera  operation,  routine  of      I 

[,       27 

Columbia  Film  Company 

I, 

Cameragraph,   Powers' 

No.  5      1 

,     189 

Comedy 

II, 

Cameragraph,   Powers' 

No.  6      1 

[,     200 

specimen 

II, 

Candy  kid 

11 

[,     208 

Competition 

II, 

Capitol  Film  Company 

[,     278 

Condensers 

I,  ^ 

Carbons,  angle  of 

[,       21 

adjustment  of  optical  sys- 

Carbons, cored 

[,       20 

tem 

I, 

Carlton   Motion-Picture 

Lab- 

adjustment    for    slides    or 

oratories 

,     278 

motion  head 

I, 

Carrier,    simple    form 

of              ] 

[,       33 

development 

I, 

Carriers     for     Americar 

I     and 

diffusion  projection 

I, 

foreign  slides 

[,       34 

emergency  projection 

I, 

Cells,  combination  of 

I] 

[,     230 

focal  lengths 

I, 

Champion  Film  Company 

[,     278 

part  of  lens 

I, 

Chase  and  trick  scrip, 

speci- 

plano-convex      condensers 

men 

I] 

[,       83 

in  pairs 

I, 

Chases 

I] 

[,       72 

Conductivity 

II, 

"Chicken  Film" 

] 

[,     278 

Cone  shutter 

I, 

Note. — For  page  numbers  see  foot  of  pages. 


286 


INDEX 


Pari 

Page 

Pari 

.  Page 

Continental  Film  Manufactur- 

Dial-regulated machine                 I 

251 

ing  Company 

I 

278 

cinephone                                    I 

254 

Continuous  projection 

I 

118 

Greenbaum                                 I 

251 

duplex  projection 

I 

118 

Diffusion  projection                        I 

31 

moving  lenses 

I 

119 

Direct-current  arc                           I 

17 

moving  mirrors 

I 

120 

Disk  shutter                                     I 

97 

moving  prisms 

I 

121 

Dissolving  lanterns                          I 

37 

steady  feed  elements 

I 

121 

alignment  masks                        I 

42 

Cored  carbons 

I 

20 

dissolving  shutters                     I 

42 

Cosmopolitan  Film  Company 

I 

278 

double                                          I 

39 

Country  theater 

II 

192 

equipment  of  second  lan- 

Cricks &  Martin 

I 

278 

tern                                       I 

43 

Croce,  Adolpho 

I 

277 

operation  of  double-lantern     I 

43 

Current  events 

II 

72 

precautions  in  dissolving        I 

44 

Current  flows,  laws  of 

II 

236 

reversals                                      I 

44 

Curvature,  remedy  for 

I 

65 

single-lantern  dissolvers           I 

43 

Curvature  of  image 

I 

64 

speed  of  change                         I 

46 

D 

triple                                             I 

37 

Dissolving  shutters                          I 

42 

Daniell  cell 

II 

227 

Double  lantern                                 I 

39 

Darkroom 

II 

27 

Double  lantern,  operation  of       I 

43 

Defender  films 

I 

278 

Double  pin  movement                    I 

104 

Dependent  machines 

I 

249 

Double  star  movement                   I 

104 

Developing  formulas 

II 

48 

Drama  scrip,  specimen                 II 

78 

acid  hypo  fixing  bath 

II 

49 

Dramas                                            II 

72 

hydro-metal  developer 

II 

48 

Drankoff  Ste.                                    I 

278 

intensification 

II 

50 

Drawn  pictures                              II 

73 

pinholes 

II 

51 

Drunken-screw  movement             I 

105 

plain  hypo  fixing  bath 

II 

48 

Dry  cell                                            II 

229 

pyro  developer 

II 

48 

Dry  film                                             I 

133 

reduction 

II 

50 

Dry  plates                                         II 

35 

removing  pyro  stains 

II 

49 

Dull  season                                      II 

205 

retouching    and    spotting 

II 

50 

Duplex  projection                            I 

118 

Developing  papers 

II 

56 

E 

Developing  prints 

II 

148 

Development 

II 

43 

Eccentric  sprocket  movement      I 

108 

developers 

II 

43 

Eclair  films                                          I 

278 

factorial 

II 

46 

Edengraph  projector                        I 

229 

fixing 

II 

47 

Edison  film  mender                         I 

155 

fixing  after  washing 

II 

47 

Edison  kinetoscope                          I 

143 

negative  image 

II 

,       43 

automatic  shutter                      I 

159 

ruby  lamp 

II 

44 

calcium      or     gaso-oxygen 

sight 

II 

44 

light                                  I 

152 

tank 

II 

46 

film  mender                                 I 

155 

trays  and  covers 

II 

44 

film  winder                                   I 

154 

washing  before  fixing 

II 

,       47 

gaso-oxygen  saturator  and 

without  red  lamp 

II 

47 

burner                              I 

158 

Note. — For  page  numbers  see  fool  of  pagse 


287 


4 

INDEX 

Part  Page 

Part 

Page 

Edison  kinetoscope 

Electromagnetism 

installation 

143 

rules  for  north  and  south 

arc  lamp 

147 

poles  of  a  helix 

11, 

233 

assembling 

143 

Electromotive  force  of  galvanic 

cone  and  bracket 

147 

cells 

11, 

220 

index  of  parts 

I,  144 

-146 

Electromotive    force    and    its 

lamp  house 

146 

measurements 

II, 

218 

operating    gaso-oxygen  li 

ght  I, 

155 

Emergency  projection 

I, 

30 

operation 

147 

Emergency  slides 

I, 

72 

carbons 

147 

Equipment     of     second     lan- 

connecting cords 

148 

terns 

I, 

43 

focusing 

148 

Essanay     Film     Manufactur- 

stereopticon lens 

148 

ing  Company 

I, 

279 

rheostats 

160 

Exposure 

II, 

35 

rules 

151 

calculation  of 

II, 

40 

take-up  device 

148 

duplicate 

II, 

42 

threading  up  film 

152 

exposure  meters 

II, 

41 

adjustable  rheostat 

153 

light  intensity 

11, 

38 

framing  device 

153 

nature  of  subject 

II, 

38 

general  instructions 

153 

plate  speed 

II, 

37 

wiring 

149 

stop  numbers 

II, 

36 

Edison    Manufacturing    Com- 

with single  lens 

II, 

42 

pany 

I, 

279 

F 

Electric  arc                            I, 

17;  II 

275 

Electric  bell 

II, 

235 

Feature  films 

II, 

200 

Electric  signs 

11, 

198 

Feeders  and  mains 

II, 

263 

Electrical    currents,    measure- 

Feed reel 

I, 

122 

ment  of 

11, 

218 

Feed-reel  magazine 

I, 

122 

Electric  principles 

II,  213 

-284 

Film 

I, 

129 

arc  lamps 

n, 

275 

care  in  handling 

I, 

130 

electricity  in  motion 

11, 

213 

care  in  projecting 

I, 

129 

electromagnetism 

n, 

232 

care  in  rewinding 

I, 

130 

laws  of  current  flow 

II, 

236 

care  in  storage 

I, 

130 

mercury-arc  rectifiers 

II, 

282 

dry 

I, 

133 

moving-picture  machines 

II, 

280 

leaders  and  tails 

I, 

133 

primary  cells 

II, 

223 

packing  for  shipment 

I, 

130 

wiring  methods 

II, 

256 

repair  of 

I, 

130 

Electrical  resistance 

II, 

221 

splicing 

I, 

131 

Electricity  in  motion 

II, 

213 

threading  up 

I, 

152 

Electromagnet 

II, 

234 

titles 

I, 

133 

Electromagnetism 

II, 

232 

warped 

I, 

134 

electric  bell 

II, 

235 

Film,  perforation  of 

II, 

119 

electromagnet 

11, 

234" 

perforating  machines 

II, 

121 

magnetic    properties    of 

a 

perforating  room 

II, 

122 

helix 

II, 

233 

shape 

II, 

120 

magnetic    properties    of 

a 

spacing 

II, 

119 

loop 

II, 

232 

Film,  storage  of 

11, 

119 

Note. — For  page  numbers  see  foot  of  pages. 


288 


INDEX 


Part  Page 

Part 

Page 

Film  basket  or  molasses  can       1 

,     127 

Fire  shutter 

I, 

100 

Film    D'Art    Film    Manufac- 

Focal lengths 

I, 

29 

turing  Company            ] 

,     279 

Focusing 

I, 

62 

Film  development                          11 

,     141 

curvature,  remedy  for 

I, 

65 

cages                                           I] 

,     141 

inclined  optical  axis 

I, 

65 

developing                                 I] 

,     142 

inclined  screen 

I, 

70 

drying                                          II 

,     142 

keystone  mask 

I, 

71 

room                                           II 

,     142 

keystone  picture 

I, 

67 

trays                                           II 

,     141 

lens  angle 

I, 

69 

washing                                      II 

,     142 

Framing  devices 

I, 

125 

Film  gate                                    I,  100,  123 

Fuse-boxes,  cut-out  panels,  etc. 

11, 

272 

adjustment     of     tension 

G 

springs                             I 

.     101 

care                                               I 

,     101 

Galvanic  cell 

II, 

214 

construction                                I 

,     101 

electromotive    forces    of 

II, 

220 

functions                                      I 

,     100 

internal  resistance  of 

II, 

222 

Film  industry,  branches  of        II 

,     112 

Galvanic  cell   and  static  ma- 

Film manufacturers                    I,  2' 

r7-282 

chine,  comparison  of 

II, 

216 

Film  mender,  Edison                      I 

,     155 

Gaso-oxygen  light,  operating 

I, 

155 

Film     shift     or     intermittent 

Gaso-oxygen     saturator     and 

movement                       I 

,     102 

burner 

I, 

158 

adjustment  of                             I 

,     116 

Gaumont  Company 

I, 

279 

beater                                         I 

,     113 

Geneva  or  pin-and-star  move- 

claw                                           I 

,     112 

ment 

I, 

102 

double  pin                                   I 

,     104 

Gnome  Motion  Picture  Com- 

double star                                  I 

,     104 

pany 

I, 

279 

drunken-screw                            I 

,     105 

Great    Northern    Film    Com- 

eccentric sprocket                      I 

,     108 

pany 

I, 

279 

intermittent  grip  mechan- 

Guard 

I, 

25 

ism                                    I 

,     115 

H 

intermittent  sprocket                I 

,     102 

modified    drunken-sere-            I 

,     107 

Hamacek  camera 

II, 

140 

pin                                                I 

,     109 

Handbills                                 II, 

200 

,  208 

pin-and-star                                I 

,     102 

Hepworth  Manufacturing  Com- 

pitman                                       I 

,     104 

pany 

I, 

279 

ratchet                                       I 

,     105 

Hispano  films 

I, 

279 

single-sprocket                          I 

,     107 

Hiring  employes 

II, 

202 

snail                                            I 

,     106 

Horsley,  David 

I, 

279 

spring  latch                               I 

,     106 

I 

Film  splicing                                     I 

,     131 

framing  by  splicing                   I 

,     132 

Image 

by  machines                                I 

,     132 

curvature     of 

I, 

64 

"in  frame"                                   ] 

,     132 

inverted 

II, 

12 

non-inflammable                        I 

,     132 

pin-hole 

11, 

11 

Film  steady  drum                            ] 

,     123 

recording 

II, 

35 

Film  winder                                      1 

,     154 

"Imp" 

I, 

279 

Financing  a  picture  theater         II 

,     175 

Inclined  optical  axis 

I, 

65 

Note. — For  page  numbers  see  foot  of  pages. 


289 


6 

INDEX 

Part  Page 

Part  Page 

Inclined  screen 

I, 

70 

Lamp 

Income  vs.  expense 

n, 

172 

adjustments                                ] 

,       20 

Independent    Moving   Picture 

alternating-current  arc             1 

,       19 

Company  of  America 

I, 

279 

angle  of  carbons                         1 

,       21 

Industrial  scrip,   specimen 

n, 

94 

centering  light                            1 

,       22 

Industrials 

II, 

71 

cored  carbons                             ] 

,       20 

Intermittent  grip  mechanism 

I, 

115 

direct-current  arc                       ] 

,       17 

Intermittent  sprocket               I, 

102 

123 

electric  arc                                  ] 

,       17 

Inverted  image 

II, 

12 

focusing  light                              ] 

,       23 

Inverted  slide 

I, 

13 

stereo  vs.  motion  arc                ] 

,       19 

Italia    Film     Manufacturing 

Lamp  adjustments                           ] 

,       20 

Company 

I, 

279 

Lamphouse                                        ] 

,       24 

K 

guard                                            '. 

,       25 

pinhole  image  peephole            '. 

,       24 

Kalem     Film     INIanufacturing 

sliding  house 

[,       24 

Company 

279 

ventilation 

,       25 

Keeping  accounts 

u, 

203 

Lantern,  elements  of 

[,       11 

Keystone  mask 

71 

inverted  slide 

[,       13 

Keystone  picture 

67 

optical  system 

[,       12 

remedy  for 

68 

placing  slide  in  holder 

[,       14 

Kinemacolor      Company      of 

thumb  spots 

[,       14 

America 

279 

Lantern  slides                          I,  72 

II,  6] 

Kinemacolor    film    pictures, 

announcement 

[,       72 

making  of 

263 

emergency 

[,       72 

Kinemacolor  machine 

267 

repair  of 

I,       73 

adjustment  of  color  screen 

268 

"Latium"  Film 

I,     279 

arc  lamp 

272 

Leaders  and  tails 

I,     133 

direction  of  film  wind 

273 

Leclanche  cell                                 I 

I,     229 

film  inspection 

271 

"Le    Lion"    Cinematographes 

framing 

270 

Company 

I,     279 

intermittent  mechanism 

267 

Lens 

I,       51 

oiling 

272 

accurate  calculations 

I,       60 

splicing 

270 

adjustable 

I,       94 

Kinephotography 

n! 

70 

calculating    lens    data    with- 

chases 

II, 

72 

out  table 

I,       57 

comedies 

n, 

72 

for  length  of  throw 

I,       59 

current  events 

II, 

72 

for  lens  length 

I,       58 

dramas 

II, 

72 

for  picture  size 

I,       58 

industrials 

II, 

71 

for  slide  size 

I,       58 

travels 

II, 

71 

care  of 

I,       61 

trick  pictures 

II, 

72 

construction    and    adjust- 

"Kineto" films 

279 

ments 

I,       61 

Kinetoscope,  Edison 

143 

corrections 

I,       51 

Kleine,  George 

279 

estimating  lens  length 

I,       57 

L 

lens  focus,  length  of 

I,       54 

Lamp 

15 

for   given   requirements 

I,       53 

acetylene 

16 

to  take  length  of  throw 

I,       91 

Note. — For  page  numbers  see  foot  of  pages 


290 


INDEX 


Part  Page 

Lens 

to  take  lens  length 

90 

to  take  picture  size 

91 

Lens  angle 

69 

Lens  printing 

58 

enlargements 

59 

Lenses 

14 

astigmatism 

22 

chromatic  aberration 

20 

diaphragm  opening 

17 

focal  length 

16 

focusing 

19 

measuring  length 

17 

spherical  aberration 

20 

Light 

centering  of 

22 

focusing  of 

23 

Lime  light 

16 

Lining  up  double  lantern 

41 

"Lion's  Head"  Film 

280 

Location  of  picture  theater 

II! 

173 

among  competitors 

n, 

173 

new  territory 

n, 

174 

small  town 

n, 

175 

Lubin    Manufacturing    Com- 

pany 

280 

Lubin  projector 

235 

Lux  Film  Manufacturing  Com- 

pany 

I, 

280 

M 

Magnetic  effect  due  to  a  charge 

in  motion  II,     213 

Magnetic  field  about  a  current, 
shape  of 

Making  titles 

Manager,  art  of 

Manifattura    Cinematografica 
Italia 

Mechanical  slide  changers 

Melies,  G. 

Mercury-arc    rectifiers   for  mo- 
tion pictures 

Metal-surfaced  screen 

Mirror  screen  II,     187 

Modified  drunken-screw  move- 
ment I,     107 

Note. — For  page  numbers  see  foot  of  pages. 


II, 

217 

n, 

143 

n, 

169 

I, 

280 

I, 

36 

I, 

280 

n, 

282 

n. 

186 

Part  Page 

Monochroming  II,     149 

Motiograph  I,     161 

how  to  install  or  set  up  I,     161 

index  of  parts  I,  179-188 

instructions  I,     170 

adjustments  I,     170 

oiling  I,     172 

lens  adjustment  I,     166 

setting  shutters  I,     174 

threading  the  film  I,     167 

Motiograph  shutters,  setting  I,     174 

Motion,  portrayal  of  I,       75 

motion  mechanism  I,       83 

perfected  motion  picture  I,       77 

persistence  of  vision  I,       81 

projection  by  persistence  of 

vision  I,       82 

proof  of  I,       76 

viewing  devices  I,       80 

Motion  head 

colormotography 

continuous  projection 

film 

film  gate 

film  manufacturers 

film    shift    or   intermittent 

movement  I, 

operator's  duties  I, 
optical  system  for  motion 

pictures  I, 

portrayal  of  motion  I, 

shutter  I, 
specific  projecting  machines    I, 

talking  pictures  I, 

threading  up  motion  head  I, 

Motion-head  lantern  I, 

auxiliary  rheostat  I, 

auxiliary  switch  I, 

Motion  head,  threading  up  I, 

automatic  rewind  I, 

feed  reel  I, 

film-basket  I, 

film  gate  I, 

film  steady  drum  I, 

framing  devices  I, 

intermittent  sprocket  I, 

lower  feed  loop  I, 


I,  75-282 
I, 
I, 
I, 
I, 

I, 


262 
118 
129 
100 
277 

102 
134 

84 

75 

95 

141 

241 

122 

47 

47 

49 

122 

126 

122 

127 

123 

123 

125 

123 

124 


291  . 


8 


INDEX 


Part  Page 
Motion  head,  threading  up 

lower  steady-feed  sprocket  I,  124 

motor  vs.  crank  I,  128 

operator's  control  of  picture  I,  128 

rewinding  !>  126 

take-up  reel  I,  124 

upper  feed  loop  I,  123 

upper  steady  feed  I,  122 

Motion  mechanism  I,  83 
Motion    Picture    Distributing 

and  Sales  Company  I,  280 
Motion  Picture  Patents  Com- 
pany of  America  I,  280 
Motion  picture,  perfected  I,  77 
Motion-picture  theater            II,  165-210 
management  II,  165 
art  of  manager  II,  169 
competition  H,  171 
income  vs.  expense  II,  172 
"sick"   motion-picture 

theater  II,  165 

theater  for  profit  II,  172 

traffic  II,  172 

operation  II,  195 

advertising  II,  197 

announcement  sUdes  II,  199 

automatic  music  II,  203 

dull  season  II,  205 

electric  signs  II,  198 

feature  films  II,  200 

handbills  II,  200 

hiring  employes  II,  202 

keeping  accounts  II,  203 

newspapers  II,  200 

noise  wagon  II,  200 

poster  service  II,  198 

printed  programs  II,  200 

program  II,  196 

renting  films  II,  202 

side  lines  for  profit  II,  207 

song  slides  II,  202 

special  program  II,  201 

studying  audiences  II,  195 

tickets  and  chopper  II,  205 

vaudeville  II,  203 

starting  a  theater  II,  173 

financing  II,  175 

Note—  For  page  numbers  see  foot  of  pages. 


Motion-picture  theater 
selecting  location 

among  competitors 

new  territory 

small  town 
special  buildings 

airdome 

country  theater 


Part  Page 

II,  173 

II,  173 

II,  174 

II,  175 

II,  188 

II,  195 

II,  192 

exclusive  picture  house       I,  189 

small  vaudeville  theater   II,  189 
store  -  front   city   theater 

building                          II,  176 

Motographic  microscopy              II,  156 

Motographic   ultramicroscopy     II,  156 

Motography  II,.  69-162 

author                                         II,  "7 

methods  of  production          II,  73 

division  of  labor                 II,  76 

early                                      II,  73 

drawn  pictures              II,  73 

photographic  process  II,  74 

separate  cameras          II,  74 

multiple  camera           II,  74 

modern                                 II,  75 

producer                                     II,  95 

product  desired                         II,  69 

reproduction                              II,  116 

salesman                                     II,  112 

Moving-picture  machine               II,  280 

arc  lamp                                     II,  280 

extra  films                                 II,  282 

handle                                         II,  282 

machines                                    II,  282 

rheostats                                    II,  281 

shutter                                        II,  282 

steel  box                                    II,  281 

top  reel                                     II,  281 

Multiple  disk  shutter                     I,  99 

N 

Navone  Film                                    I,  281 

"Nestor"  Films                                I,  281 

Newspaper  advertising                  II,  200 
New    York     Motion    Picture 

Company                        I,  281 

Noise  wagon                                  II,  200 


292 


INDEX 


O 

Ohm's  law 

applications  of 
divided  circuits 
fall  of  potential  in  cir- 
cuit 
joint    resistance    of    di- 
vided circuits 
series  circuits 
simple  applications 
Operation  of  double  lantern 
Operation  of  a  picture  theater 
Operator's  control  of  picture 
Operator's  duties 

before  show  begins 
conducting  program 
keeping  up  with  times 
preparing  for  projection 
Optical  lantern 
condensers 
dissolving  lanterns 
elements  of  lantern 
focusing 
lamp 

lamphouse 
lantern  slides 
lens 

motion-head  lantern 
slide  carrier 
Optical  system 

adjustment  of 
Optical  system  for  motion  pic- 
tures 
accurate  calculations 
adjustable  lenses 
approximate  calculations 
condensers 
as  a  pair 
back 
front 

short  rules  for  lengths 
lamp 
lenses 

matched  lenses  (stereo  and 
motion  head) 
Orthochromatic  photography 
Outlet  boxes 
Outlets,  location  of 

Note. — For  page  numbers  sec  fool  of  pages. 


Part 

Page 

P 

Part 

Page 

n, 

222 

Packing  films  for  shipments 

II, 

154 

II, 

248 

Panoramas 

II, 

62 

II, 

252 

Paragon  Bioscope  Company 

I, 

281 

Pathe  Freres 

I 

281 

II, 

250 

Pathe  professional  model  pro- 

jector 

I 

206 

II 

254 

Photographer 

II 

116 

II, 

249 

Photographic  equipment 

II 

155 

II, 

248 

buying  cameras 

II 

155 

43 

buj'ing  films 

II 

155 

II 

195 

fire  risk  in  storing  films 

II 

155 

128 

making  cameras 

II 

155 

134 

Photographic  factory,  division 

134 

of 

II 

116 

135 

Photographs,  colored 

II 

64 

137 

Photography 

II, 

11-66 

135 

mechanical  details 

II 

11 

I,' 

11-73 

orthochromatic 

II 

64 

25 

printing 

II 

51 

37 

recording  image 

II 

35 

11 

special  application  of 

II 

61 

62 

theory 

II 

11 

15 

tri-color 

II 

65 

24 

Piccadilly  Circus 

I 

281 

72 

Picture  house,  large  exclusive 

II 

189 

51 

Pictures   without   studios 

II 

103 

47 

Pin  movement 

I 

109 

33 

Pin-cross  movement 

I 

108 

12 

Pin-hole  image 

II 

11 

31 

Pin-hole  image  peephole 

I 

24 

Pitman  movement 

I 

104 

84 

Plano-convex     condensers    in 

92 

pairs 

I, 

28 

94 

Plate-holder 

II 

26 

92 

Polarization 

II, 

226 

84 

bichromatic  cell 

II 

226 

87 

Daniell  cell 

II 

227 

84 

dry  cell 

II 

229 

86 

Leclanche  cell 

II 

229 

88 

Polyscope,  Selig 

I 

225 

84 

Portrayal  of  motion 

I 

75 

88 

Poster  service 

II, 

198 

Powers  Company 

I, 

281 

93 

Powers'  No.  5  cameragraph 

I, 

189 

II! 

64 

Powers'   No.   6  cameragraph 

I, 

200 

II, 

269 

Primary  cells 

II, 

223 

II, 

258 

action  of  a  simple  cell 

II, 

223 

293 


10 


INDEX 


Part  Page 

I 

'art 

Page 

Primary  cells 

Producing  a  drama 

combination  of  cells 

II, 

230 

rewriting 

n, 

110 

polarization 

n, 

226 

titles 

II, 

110 

storage  battery 

II, 

231 

Producing  image 

II, 

28 

Print  spotting 

II, 

149 

background 

II, 

29 

Printed  program 

n, 

200 

composition  and  balance 

II, 

31 

Printing 

11,51 

144 

distortions 

II, 

34 

developing  papers 

n, 

56 

horizon  line 

II, 

32 

developing  prints 

11, 

148 

lighting 

II, 

30 

exposure 

n, 

146 

point  of  view 

II, 

32 

film      adjustment      durin 

g 

principal  object 

II, 

29 

printing 

n. 

147 

prominence  of  background 

II, 

32 

hand  staining 

11, 

150 

rising  front 

11, 

35 

inspection 

11, 

148 

size  of  object 

II, 

30 

lens  printing 

II, 

58 

swing  back 

II, 

34 

machines 

II, 

144 

Program 

II, 

196 

making  exposure  ticket 

II, 

148 

Program  advertising 

II, 

208 

print  spotting 

II, 

149 

Projection 

I, 

118 

printing  frame 

II, 

52 

Projection  with  Edison  lenses 

I, 

161 

printing-out  papers 

II, 

52 

Projectors 

processes 

II, 

51 

Edengraph 

I, 

229 

repeater  printing 

II, 

150 

Lubin 

I, 

235 

room 

II, 

144 

Pathe  professional  model 

I, 

206 

self-toning  paper 

II, 

55 

Properties  and  costumes 

II, 

105 

staining 

II, 

149 

R 

toning  or  monochroming 

II, 

149 

Printing-out  papers 

II, 

52 

Ratchet  movement 

I, 

105 

chloride  papers 

II, 

52 

Raw  film 

II, 

117 

combined  toning  and  fixing  II, 

55 

coating 

II, 

118 

final  washing 

54 

composition 

II, 

117 

fixing 

54 

manufacture 

II, 

117 

stopping 

54 

non-inflammable 

II, 

118 

toning 

53 

Recording  image 

II, 

35 

washing  before  toning 

53 

development 

II, 

43 

Producer  of  picture 

95 

dry  plates 

II, 

35 

actors 

105 

exposure 

II, 

35 

pictures  without  studios 

103 

films 

II, 

35 

producing  a  drama 

107 

Rehearsals 

II, 

106 

properties  and  costumes 

105 

"Reliance" 

I, 

281 

rehearsals 

106 

Renting  films 

II, 

202 

studio  lighting 

101 

Repair  of  slides 

I, 

73 

studio  scenes 

96 

Reproduction 

II, 

116 

Producing  a  drama 

107 

camera 

II, 

122 

final  criticism 

111 

camera  man 

II, 

122 

motion  scenes 

108 

camera  man's  duties 

II, 

128 

padding 

109 

chromophotography 

II, 

155 

review  and  criticism 

109 

coloring  films 

11, 

151 

Note. — For  page  numbers  see  fool  of  pages. 


294 


INDEX 


11 


Part 

Page 

Part  Page 

Reproduction 

Shutters                                     I,  95; 

11,24 

development     of  films 

11, 

141, 

automatic                                   j 

,     159 

factory  floor  plan 

11, 

140 

cap                                              I] 

,       24 

making  titles 

n, 

143 

curtain                                       I] 

,       24 

packing  films  for  shipment 

11, 

154 

fire                                                ] 

,     100 

perforation  of  films 

n, 

119 

focal  plane                               i; 

,       25 

photographer 

II, 

116 

leaf                                              11 

,       24 

photographic  equipment 

II, 

155 

setting                                          ] 

,     100 

photographic  factory- 

II, 

116 

testing                                        I] 

,       25 

printing 

II, 

144 

types  of                                       ] 

,       97 

raw  film 

II, 

117 

barrel                                      ] 

,       97 

reclaiming  waste 

II, 

154 

before-the-Iens                     ] 

,       98 

storage  of  film 

II, 

119 

cone                             -         ] 

,       99 

trick  pictures 

II, 

156 

disk                                         ; 

,       97 

waterproofing 

II, 

154 

multiple-disk                         ] 

,       99 

Resistance 

II, 

236 

Sicania  Film  Factory 

,     281 

affected  by  heating 

II, 

242 

"Sick"  motion-picture  theater     I. 

,     165 

calculation  of 

II, 

239 

Side  lines  for  profit                        L 

,     207 

inversely    proportional    to 

advertising  drop  curtain         L 

,     207 

cross-section 

II, 

237 

advertising  slides                      1. 

,     207 

proportional  to  length 

11, 

236 

candy  kid                                  I] 

,     208 

specific  resistance 

II, 

238 

handbills                                    11 

,     208 

Reversals 

I, 

44 

program  advertising                I] 

,     208 

Revier  Motion  Picture  Com- 

refreshment annex                   I] 

,     210 

pany 

I, 

281 

sheet  music  sales                      I] 

,     210 

Rewinding  of  film 

I, 

126 

wall  posters                               11 

,     207 

Rheostats 

I, 

160 

Sight  development                         I] 

,       44 

Ruby  lamp 

II, 

44 

Sign  flasher                                     I] 

,     199 

S 

Simple  cell,  theory  of  action  of   I] 

,     224 

Single-lantern  dissolvers                 ] 

,       43 

Salesman 

II, 

112 

Single-sprocket  movement             ] 

,     107 

advance  shipment 

II, 

114 

sHde  ahgnment                           ] 

,       45 

branches  of  film  industry 

II, 

112 

Slide  carrier                                      ] 

,       33 

factory  schedule 

II, 

114 

American  and  foreign               ] 

,       34 

lectures 

II, 

112 

simple  form  of                            ] 

,       33 

release  dates 

II, 

113 

slide-window  masks                   ] 

,       34 

sales  contracts 

n, 

115 

slide-window  shutters                ] 

,       35 

selling  methods 

II, 

112 

slip  slide                                      ] 

,       35 

title  posters 

II, 

116 

Slide,  inverted                                  ] 

13 

Scenario 

II, 

78 

Slide-window  masks                        ] 

,       34 

Second  lantern,  equipment  of 

I, 

43 

Slide-window  shutters                     1 

,       35 

Self-toning  paper 

II, 

55 

Slides 

blue  prints 

II, 

55 

inverted                                       ] 

,       13 

sepia 

II, 

56 

storage  of                                    1 

,       37 

Selig  polyscope 

I, 

225 

Sliding  house                                    1 

,       24 

Selig  Polyscope  Company 

I, 

281 

Slip  slide  carrier                               1 

,       35 

Sheet  music  sales 

II, 

210 

Slot  machines                                 I] 

,     209 

Note. — For  page  numbers  see  foot  of  pages. 


295 


12 


INDEX 


Part 

Page 

Small  vaude\nlle  theater 

11, 

189 

Snail  movement 

I, 

106 

Societe  Cines 

I, 

281 

Solax  Company 

I, 

281 

Song  slides 

n, 

202 

Special  biiildings 

II, 

188 

airdome 

II, 

195 

countrj-  theater 

II, 

192 

large  exclusive  picture  house  II, 

189 

small  vaudeville  theater 

II, 

189 

Special  programs 

II, 

201 

amateur  night 

n, 

201 

contests 

11, 

201 

double  price 

II, 

202 

school  children 

II, 

201 

Specific    projecting    machines 

I, 

141 

Edengraph  projector 

I, 

229 

Edison  kinetoscope 

I, 

143 

Lubin  projector 

I, 

235 

Motiograph 

I, 

161 

Pathe    professional    model 

projector 

I, 

215 

Powers'  No.  5  cameragraph 

I, 

189 

Powers'  No.  6  cameragraph 

I, 

200 

Selig  polyscope 

I, 

225 

Standard  projector 

I, 

220 

Specific  resistance 

II, 

238 

Speed  of  change 

I, 

46 

Spherical  aberration 

II, 

20 

Spring  latch  movement 

I, 

106 

Staining 

II, 

149 

Standard  projector 

I, 

216 

index  of  parts 

I, 

220 

rewinding  of 

I, 

223 

Stereo  vs.  motion  arc 

I, 

19 

Stereographs 

II, 

62 

Stop  picture 

II, 

161 

Storage  battery 

II, 

231 

Storage  of  slides 

I, 

37 

Store-front  city  theater  build- 

ing 

II, 

176 

elaborate  store  front 

II, 

181 

floor  plan 

II, 

177 

lighting  methods 

II, 

179 

low-cost  store  front 

II, 

179 

picture  screen 

n, 

186 

sloping  floor 

II, 

184 

Part  Page 
Store-front  city  theater  build- 
ing 

specimen  expense  sheet  II,  184 

stage  II,  185 

weekly  expense  sheet  II,  183 

Studio  Hghting  II,  101 

artificial  II,  101 

daylight  II,  102 

glass  house  tj^pe  II,  102 

turntable  type  II,  103 

yard  studio  type  II,  103 

Studio  scenes  II,  96 

Sunny  South  Film  Company  I,  281 

Synchronous  electric  motor  I,  246 


Tables 

American  wire  gauge  (B.  & 
S.) 

day  and  hour  exposure 
chart 

equivalent  stop  numbers  in 
focal-factor  and  uni- 
form systems 

exposure  chart 

lens  data 

primary'  cells,  electromo- 
tive force,  resist- 
tance,  etc.  II, 

relative  resistance  of  chem- 
icall}^  pure  sub- 
stances at  32  F.  in- 
ternational ohms 

screen  image,  size  of  when 
moving  picture  films 
are  projected 

Stubs'  or  Birmingham  Wire 
Gauge  (B.W.G.) 

temperature    coefficients 

wires,  carrying  capacity  of 
Take-up  reel 
Talking-picture  camera 
Talking  pictures 

dependent  machines 

dial-regulated  machine 

length  of  records 

manufacture 


II,     244 
II,       39 


II,       37 

II,     135 

I,       55 


246-247 


II,     240 


I,       89 


II, 

245 

II, 

243 

II, 

274 

124 

257 

241 

249 

251 

244 

255 

Note. — For  page  numbers  see  foot  of  pages. 


296 


INDEX 


13 


Part 

Page 

Part 

Page 

Talking  pictures 

Urban,   Chas.,  Trading  Com- 

recording sound 

I, 

242 

pany 

I, 

282 

reproduction  of 

I, 

258 

V 

synchronism 

.   I, 

242 

unitary  machines 

I, 

245 

Vaudeville 

II, 

203 

Telephotography 

n, 

63 

Ventilation 

I, 

25 

Tension  springs,  adjustment  of 

I, 

101 

Viewing  devices 

I, 

80 

Thanhouser  Company 

I, 

281 

Vision 

Theater,  starting 

n, 

173 

persistence  of 

I, 

81 

Threading  up  motion  head 

I, 

122 

projection  by  persistence  of 

I, 

82 

Thumb  spots 

I, 

14 

Vitagraph  Company  of  America   I, 

282 

Tickets  and  chopper 

n, 

205 

Title  posters 

II, 

116 

W 

Titles 

I, 

133 

Wall  posters 

II, 

207 

Titles,  framing  of 

I, 

270 

Warped  film 

I, 

134 

Toning 

n, 

149 

Warwick  Trading  Company 

I, 

282 

Traffic 

11, 

172 

Waterproofing 

II, 

154 

Travel  and  comedy  scrip,  speci- 

Wiring methods 

II, 

256 

men 

11, 

92 

outlet  boxes,  cut-out  pan- 

Travel scrip,  specimen 

II, 

90 

els,  etc. 

II, 

269 

Travels 

II, 

71 

planning  an  installation 

II, 

256 

Trick  notes 

II, 

87 

Wiring  an  office  building 

II, 

264 

Trick  pictures                             II,  72 

,  156 

basement 

II, 

265 

blackroom 

II, 

160 

character  of  load 

II, 

265 

dissolving  views 

n. 

159 

electric  current  supply 

II, 

264 

double  exposures 

II, 

159 

feeders  and  mains 

II, 

265 

double  printing 

II, 

159 

first  floor 

II, 

268 

dummies 

II, 

157 

interconnection  system 

II, 

268 

ghosts 

II, 

158 

second  floor 

11, 

268 

mirrors 

II, 

160 

switchboard 

II, 

264 

reversals 

II, 

157 

upper  floors 

II, 

268 

speed  pictures 

II, 

157 

"Wrench"  Films 

I, 

282 

stop  picture 

II, 

161 

X 

Tri-color  photography 

II, 

65 

Triple  lantern 

I, 

37 

X-Ray  motography 

II, 

156 

Tyler  Film  Company 

I, 

282 

Y 

U 

Yankee  Film  Company 

I, 

282 

Unitary  machines 

I, 

245 

Z 

Unitas     Film     Manufacturing 

Company 

I, 

282 

Zoetrope 

11, 

73 

Nole. — For  page  numbers  see  foot  of  pages. 


297 


37 


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